World of Warships: Legends ship guide

Iwami

Also called: 石见 Beta
Japan · Tier VIII · Battleship · Premium
Torpedo battleshipDeck torpedoes back the main guns; the torps are a brawl-range trap.
Playstyle
  • Anchor a flank at 14-17 km where flanking ships have to cross your torpedo arcs to push
  • The torpedoes are a deterrent that closes off whole lanes (under 15 km threat)
  • Avoid: Drifting broadside to set up a torpedo launch
Key characteristics
Long, heavy torpedoes (15 km)Punchy HE secondariesThick citadel floorVisible torps
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Playstyle

Overview

Iwami is a Tier VIII Japanese torpedo-equipped battleship: she carries deck torpedoes reaching 15 km on a hull most BBs lack. The torps are a brawl-range threat that forces approaching ships to peel off or eat a wave; the main battery is the primary damage source, the torps are the trap. Standout traits: best punchy HE secondaries in T8 BBs (2,600) and top-decile heavy secondary DPM in T8 BBs (330,500).

Positioning

Anchor a flank at 14-17 km where flanking ships have to cross your torpedo arcs to push. The torpedoes are a deterrent that closes off whole lanes (under 15 km threat); use that pressure to force enemies into your main battery, then dump torps as a finisher when they commit. Bow on between salvos to keep the citadel angled.

Potato Avoidance

Drifting broadside to set up a torpedo launch

The torpedoes are a trap that closes a lane, not a primary weapon; turn out of a launch if the angle exposes the citadel, and use the threat alone to force lane choices. A dead torpedo BB never drops a torp.

Signature Traits

ELITE SECONDARIES
  • Punchy HE · 2600 max
  • Heavy secondary DPM · 330500 secondary
Long-range torps

15 km torpedo range, best of the 7 T8 BBs with torpedoes.

Thick citadel floor

50 mm citadel bottom, best of T8 BBs. Deep-water torps and underwater pen do less.

MIXED TORPEDOES
  • Visible torps · 2.2 km
  • Slow torp reload · 150 s
Acquisition

How to get Iwami

Iwami is a Premium ship and not available to unlock in the Tech Tree. Acquisition paths: Containers, Doubloons, and Campaign. Container chances are shown as the listed odds of receiving this exact ship, dividing grouped ship-pool odds across the resolved ships and including nested container paths when a crate can drop another crate.

Best listed chance for this ship

  • Super VIII crate 5% One of the Tier VIII Premium ships Event · Super VIII crate · 1 of 20 ships
  • Santa Level 5 1.25% Tier VIII Premium ship Archived · Santa Level 5 · 1 of 10 ships
  • Spectral Vault 5.0 0.657895% Tier VIII Premium ship Archived · Spectral Vault 5.0 · 1 of 19 ships
Show all 13 containers (10 more)
  • Santa Level 4 0.425% Tier VIII Premium ship Archived · Santa Level 4 · 2 paths combined · 1 of 10 ships
    Show 2 paths
    • Santa Level 40.3%
    • Santa Level 4 → Santa Level 50.125%
  • Spectral Vault 4.0 0.256579% Tier VIII Premium ship Archived · Spectral Vault 4.0 · 2 paths combined · 1 of 19 ships
    Show 2 paths
    • Spectral Vault 4.00.157895%
    • Spectral Vault 4.0 → Spectral Vault 5.00.098684%
  • Santa Level 3 0.13625% Tier VIII Premium ship Archived · Santa Level 3 · 4 paths combined · 1 of 10 ships
    Show 4 paths
    • Santa Level 3 → Santa Level 50.0625%
    • Santa Level 3 → Santa Level 40.045%
    • Santa Level 3 → Santa Level 4 → Santa Level 50.01875%
    • Santa Level 30.01%
  • Spectral Vault 3.0 0.053224% Tier VIII Premium ship Archived · Spectral Vault 3.0 · 4 paths combined · 1 of 19 ships
    Show 4 paths
    • Spectral Vault 3.0 → Spectral Vault 5.00.019737%
    • Spectral Vault 3.0 → Spectral Vault 4.00.017368%
    • Spectral Vault 3.0 → Spectral Vault 4.0 → Spectral Vault 5.00.010855%
    • Spectral Vault 3.00.005263%
  • Mystic Lantern 0.045455% Tier VIII Premium ship Event · Mystic Lantern · 1 of 22 ships
  • Santa Level 2 0.041688% Tier VIII Premium ship Archived · Santa Level 2 · 6 paths combined · 1 of 10 ships
    Show 6 paths
    • Santa Level 2 → Santa Level 40.015%
    • Santa Level 2 → Santa Level 3 → Santa Level 50.009375%
    • Santa Level 2 → Santa Level 3 → Santa Level 40.00675%
    • Santa Level 2 → Santa Level 4 → Santa Level 50.00625%
    • Santa Level 2 → Santa Level 3 → Santa Level 4 → Santa Level 50.002812%
    • Santa Level 2 → Santa Level 30.0015%
  • Champion's Box 0.02725% Tier VIII Premium ship Archived · Champion's Box · 4 paths combined · 1 of 10 ships
    Show 4 paths
    • Champion's Box → Santa Level 3 → Santa Level 50.0125%
    • Champion's Box → Santa Level 3 → Santa Level 40.009%
    • Champion's Box → Santa Level 3 → Santa Level 4 → Santa Level 50.00375%
    • Champion's Box → Santa Level 30.002%
  • Spectral Vault 2.0 0.010454% Tier VIII Premium ship Archived · Spectral Vault 2.0 · 6 paths combined · 1 of 19 ships
    Show 6 paths
    • Spectral Vault 2.0 → Spectral Vault 4.00.003158%
    • Spectral Vault 2.0 → Spectral Vault 3.0 → Spectral Vault 5.00.001974%
    • Spectral Vault 2.0 → Spectral Vault 4.0 → Spectral Vault 5.00.001974%
    • Spectral Vault 2.0 → Spectral Vault 3.0 → Spectral Vault 4.00.001737%
    • Spectral Vault 2.0 → Spectral Vault 3.0 → Spectral Vault 4.0 → Spectral Vault 5.00.001086%
    • Spectral Vault 2.0 → Spectral Vault 3.00.000526%
  • Santa Level 1 0.009878% Tier VIII Premium ship Archived · Santa Level 1 · 8 paths combined · 1 of 10 ships
    Show 8 paths
    • Santa Level 1 → Santa Level 3 → Santa Level 50.003125%
    • Santa Level 1 → Santa Level 2 → Santa Level 40.00225%
    • Santa Level 1 → Santa Level 2 → Santa Level 3 → Santa Level 50.001406%
    • Santa Level 1 → Santa Level 2 → Santa Level 3 → Santa Level 40.001012%
    • Santa Level 1 → Santa Level 2 → Santa Level 4 → Santa Level 50.000938%
    • Santa Level 1 → Santa Level 30.0005%
    • Santa Level 1 → Santa Level 2 → Santa Level 3 → Santa Level 4 → Santa Level 50.000422%
    • Santa Level 1 → Santa Level 2 → Santa Level 30.000225%
  • Spectral Vault 1.0 0.001295% Tier VIII Premium ship Archived · Spectral Vault 1.0 · 9 paths combined · 1 of 19 ships
    Show 9 paths
    • Spectral Vault 1.0 → Spectral Vault 2.0 → Spectral Vault 4.00.000284%
    • Spectral Vault 1.0 → Spectral Vault 3.0 → Spectral Vault 5.00.000197%
    • Spectral Vault 1.0 → Spectral Vault 2.0 → Spectral Vault 3.0 → Spectral Vault 5.00.000178%
    • Spectral Vault 1.0 → Spectral Vault 3.0 → Spectral Vault 4.00.000174%
    • Spectral Vault 1.0 → Spectral Vault 2.0 → Spectral Vault 3.0 → Spectral Vault 4.00.000156%
    • Spectral Vault 1.0 → Spectral Vault 3.0 → Spectral Vault 4.0 → Spectral Vault 5.00.000109%
    • Spectral Vault 1.0 → Spectral Vault 2.0 → Spectral Vault 3.0 → Spectral Vault 4.0 → Spectral Vault 5.00.000098%
    • Spectral Vault 1.0 → Spectral Vault 3.00.000053%
    • Spectral Vault 1.0 → Spectral Vault 2.0 → Spectral Vault 3.00.000047%
Official WG availability sources
  • Silver Tsurugi Campaign Breakdown Campaign Start: 2023-04-10 · End: 2023-05-14 Official campaign breakdown naming this ship as a campaign/reward-context ship; explicit source windows are used when present, otherwise the end date is inferred from the next indexed campaign breakdown when available.
  • Official WoWS Legends container odds Containers Official container drop rows linked below include direct and nested effective ship odds.
  • Through the Spy Glass: Iwami Ship feature / release Start: 2023-04-12 · End: open/unknown end Official Through the Spy Glass feature for this ship; useful as a release/availability source, but not a guaranteed current-store listing.
  • Anniversary Update: Operation Piñata 17,500 Doubloons 2025-07-31 Tier VIII default; exact price not in source
Show direct source rows

Want the full picture? Each container page charts the odds as you open more crates - including pity guaranteed-reward timers and, for GD Supporters, pack math personalized to your port.

Builds

Pair with a commander whose unique skill complements her main armament; check the build tool for current recommendations.

Takeo Takagi

WG official

WG official build from Through the Spy Glass: Iwami.

Source: Through the Spy Glass: Iwami

Open in Build Tool →

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Cohort position

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Where Iwami sits among Tier VIII BBs (31 ships). Notable standouts are shown first; the rest of the cohort-ranked stats are in the expand below. Acquisition variants (Black Friday, Founders Edition) are counted once with their base ship, not as separate peers.

BestSecondary HE alpha2,600 (1 of 6 tied) BestTorpedo range15 km (1/7) Top 10%AP shell damage13,600 (4/32) Top 10%Secondary DPM (per side)330,500 (4/32) Top 25%Hit points80,700 HP (8/32) Top 25%Main battery caliber410 mm (8/32) Top 25%Main battery reload22.5 s (5/32) Top 25%HE shell damage6,500 (7/30) Top 25%Main dispersion207.7 m (6/32) Top 25%Secondary fire chance10% (8/30) Bottom 25%Fires per minute6.4 (24/30) Bottom 25%Turn-speed retention164.8 hp/m (25/32) Bottom 25%Power-to-weight2.46 hp/t (25/32) WorstTorpedo reaction time11.7 s (7/7) WorstTorpedo reload150 s (1 of 2 tied)
See 39 mid-pack stats

Not standouts for Iwami -- here's where she sits on every other ranked stat in the cohort. Stats tagged NORM are tied across more than half the cohort, so the value is the cohort default rather than a standout.

Max speed28.2 kt(22/32) Concealment15.84 km(21/32) Smoke fire bloom15.4 km(24/32) Air detection12.67 km(21/32) Rudder shift17.2 s(22/32) Turning circle880 m(13/32) Traverse-to-turn ratio5.44 ×(12/32) Main battery range17.18 km(17/32) Sigma1.9(11/32) HE DPM138,667(10/30) AP DPM290,133(11/32) Secondary HE pen26 mm(9/30) AP velocity834 m/s(11/32) HE velocity834 m/s(9/30) Acceleration36.5 s(13/32) AP arming threshold68 mm(17/32) Engine power145,000 hp(23/32) Displacement58,962 t(21/32) AP pen at 10 km611 mm(19/32) Effective HE DPM (incl. fire)191,129(17/30) Secondary range6 km(11/32) AA DPS531(17/32) AA range5 km(18/32) AA threat1,925(16/32) Flak per wave (expected)1,725(11/32) Torpedo damage≈19,567(3/7) Torpedo speed70 kt(3/7) Repair charges3(13/32) Max armor410 mm(11/32) Citadel belt360 mm(11/30) Deck armor75 mm(10/29) NormSecondary dispersion bracket57(25 of 32 tied at this value) NormAP fuse timer0.03 s(29 of 32 tied at this value) NormAP ricochet start45°(28 of 32 tied at this value) NormAP auto-bounce angle60°(28 of 32 tied at this value) NormTurn speed retained81%(31 of 32 tied at this value) NormRepair heal rate0.5 %/s(23 of 32 tied at this value) NormBow armor32 mm(28 of 30 tied at this value) NormStern armor32 mm(28 of 30 tied at this value)
Survivability
Hit Points80,700
Displacement58,962 t
Hull dimensions
ƒLength x beam at the waterline, with the hull's draft where the client carries one. Ships whose client entry holds only the 260 x 20 m placeholder use a curated real-world figure instead, and any ship we have no trustworthy size for omits this row rather than print the placeholder. Length matters when dodging torpedoes; beam and draft shape how hard the ship is to hit.
255.2 x 37.4 m
Armor range19–410 mm
Plate armor thicknesses19, 25, 32, 38, 45, 50, 51, 55, 75, 76, 93, 102, 108, 115, 127, 140, 152, 191, 203, 229, 254, 305, 356, 360, 380, 410 mm
Armor material/layer entries81
Fire resistance
ƒDoes not reduce the damage a burning fire does per second: replay-measured burn ticks run at the full rate on every ship. By elimination it lowers how often hits set you on fire; ignition-rate replay data is consistent with that but too confounded by attacker mix to measure the reduction directly.
40%
Fire duration60 s
Fire damage
ƒEach fire ticks 0.3% of max HP per second for the full 60 s, so one unattended fire burns 18% of the pool (14,526 HP on this ship). 4 fire points can burn at once. Verified against measured burn ticks in replay data.
0.3% of HP per second
Flood duration40 s
Flood damage
ƒA flood ticks 0.5% of max HP per second for the 40 s duration, so one unattended flood costs 20% of the pool (16,140 HP on this ship). Verified against measured flood ticks in replay data.
0.5% of HP per second
Torp Reduction
ƒReduces torpedo hit damage. Replay data shows no effect on floods: flood ticks run at the full rate and flood frequency does not decline with protection.
37%
Magazine HP
ƒPer-turret powder-magazine HP, a separate pool from the ship's. Penetrating hits wear it down and the turret is likelier to be knocked out as it falls, so a larger pool keeps the guns firing through punishment that silences a peer's.
40,400
Steering gear HP
ƒDurability of the steering gears. As this pool drops, hits are likelier to jam the rudder; unlike most modules the steering can be knocked out and repaired but is never permanently destroyed.
24,200
Effective HP
ƒBase 80,700 HP plus everything Repair Party can restore: 0.5%/s x 28 s = 11,298 HP per charge, x3 charges = 33,894 HP. Ceiling, not a prediction: a charge only restores damage actually taken, and only the regeneratable share of it. Across 1,826 players in our replay corpus the median ship realized about half of this, mostly because half the charges go unspent — when Repair Party IS pressed it returns ~97% of the per-charge figure above.
114,594
Repairable: penetration50%
Repairable: citadel10%
Repairable: steering gear50%
Main Battery
ModuleArtillery: 410 mm/50 10th Year Type mod. A
Mounts / barrels4 mounts / 8 barrels
Reload time25 s
Firing range17.2 km
Turret traverse5.14 °/s
Turret armor508 mm
Turret traverse arcs
ƒHow far each mount can train, in degrees to either side of the mount's own facing, read from in-game data. A rear turret with ±150° leaves a 60° blind wedge over the bow; one-sided arcs are wing mounts that cover a single side. The data does not say which way each mount faces, so the arcs are listed per mount without bow/stern angles.
2x ±153°, 2x ±155°
Guns to bear
ƒHow far off the bow (or stern) the ship must angle before every main turret can fire: the widest blind wedge among the rear-facing (or forward-facing) mounts, from each mount's trainable arc. Mount facing is inferred from turret stations and verified against known layouts, including Izumo's aft-facing forward turret.
25° off bow / 27° off stern
AP pen max range487 mm
HE fire DPM vs T8 BB47216
Effective HE DPM vs T8 BB172016
Shell Grouping (σ)1.9
Max Horiz Disp
ƒHorizontal dispersion ellipse width at max range, from the verified WoWS dispersion model: σH=(R30·idealRadiusminRadiusidealDistance+minRadius)·30 =(1717730·102.81000+2.8)·30=207.7m
207.7 m at 17.2 km
Max Vert Disp
ƒVertical dispersion ellipse height at max range: σV=σH·radiusOnMax =207.7·0.8=166.1m
166.1 m at 17.2 km
Med Horiz Disp
ƒ50%-hit horizontal radius: σH,50=σH·0.6σ =207.7·0.61.9=65.6m
65.6 m at 17.2 km
Med Vert Disp
ƒ50%-hit vertical radius: σV,50=σV·0.6σ =166.1·0.61.9=52.5m
52.5 m at 17.2 km
Turret turn time
ƒ180 degrees / 5.14 deg/s traverse speed = 35 s.
35 s
Shells/min
ƒZero upgrades: 8 broadside guns x 60 / 25 s base reload = 19.2. All upgrades (Main Battery Mod. 3 = -10% reload): 8 broadside guns x 60 / 22.5 s all-upgrades reload = 21.3.
Initial: 19.2 → 21.3
HE shells
HE Damage6,500
HE Velocity834 m/s
Fire Chance30%
HE penetration
ƒ68 mm ≈ 410 mm caliber / 6 (standard HE penetration ratio).
68 mm
HE full-salvo alpha
ƒ6,500 HE damage x 8 broadside guns = 52,000.
52,000
HE DPM
ƒZero upgrades: 52,000 HE full-salvo alpha x 60 / 25 s base reload = 124,800. All upgrades (Main Battery Mod. 3 = -10% reload): 52,000 HE full-salvo alpha x 60 / 22.5 s all-upgrades reload = 138,667.
Initial: 124,800 → 138,667
Fires/min
ƒZero upgrades: 19.2 shells/min x 30% fire chance = 5.76. All upgrades (Main Battery Mod. 3 = -10% reload): 21.3 shells/min x 30% fire chance = 6.4.
Initial: 5.76 → 6.4
AP shells
AP Damage13,600
AP Velocity834 m/s
Min Ricochet45 deg
Guaranteed Ricochet60 deg
Fuse Timer0.033 s
Fuse Threshold68 mm
AP overmatch
ƒfloor(410 mm caliber / 14.3) = 28 mm (AP auto-penetrates plating this thick or less).
28 mm
AP Pen Close
ƒCanonical community AP formula (jcw780/wows_shell), evaluated at muzzle velocity: P=107·K·m0.69·d1.07·v01.38 =107·2650·10200.69·0.411.07·8341.38=880.5mm. Matches the in-game spec card.
880.5 mm point-blank
AP Pen Far
ƒSame formula at the ship's max firing range (17.2 km), where the shell has slowed to 542.2 m/s: P=107·2650·10200.69·0.411.07·542.21.38=486mm.
486 mm at 17.2 km
AP full-salvo alpha
ƒ13,600 AP damage x 8 broadside guns = 108,800.
108,800
AP DPM
ƒZero upgrades: 108,800 AP full-salvo alpha x 60 / 25 s base reload = 261,120. All upgrades (Main Battery Mod. 3 = -10% reload): 108,800 AP full-salvo alpha x 60 / 22.5 s all-upgrades reload = 290,133.
Initial: 261,120 → 290,133
AP AOE Radius
ƒAP shell over-penetration splash radius; scales with shell mass. Wickes 102mm = 3, standard 152mm CL ~ 20, Iowa 406mm ~ 270, Yamato 460mm = 400, Incomparable 650mm = 550 (max). Larger value = bigger splash damage area when AP over-pens.
250
Torpedoes
ModuleTorpedoes: 610 mm quadruple
Launchers / tubes2 launchers × 4 tubes = 8 tubes
Reload time150 s
Projectile speed70 kt
Range15 km
Maximum simulated damage
ƒEstimate of WG's in-game value; matches the in-game port screen within ±5%. Saturation: most targets only intersect one hull section, so the sim transfers ~1/3 of the warhead alpha (2/3 when the warhead blast >= 5000 and the burst reaches a second section). For this ship: Dsim=α·c=58,700·0.333=19,567.
≈ 19,567
Maximum damage (ammunition)
ƒThe ammunition card's 'Maximum Damage' stat, exact: warhead alpha / 3 plus the blast addend. This is the per-torpedo number most references quote; the 'Maximum simulated damage' row above is WG's separate geometry-sim stat from the launcher spec panel.
20,967
Torpedo detectability2.2 km
Reaction time
ƒHow long a target has to dodge after your torpedo is spotted at its detectability range (lower means less warning): treact=2.2 km70 kt×2.6855=11.7 s. The 2.6855 m/s-per-knot game-speed factor is calibrated from in-game measurement; the community's traditional 2.6 reads about 3% slower. Base value; commander torpedo-concealment skills lower it further. Community torpedo-reaction calculator by u/LorenDovah and u/The_ColorOutofSpace.
11.7 s
Flooding chance
ƒRead straight from the game's own data: this torpedo carries a flooding-chance value of 3.55 per hit, shown as 3.55×100=355%. Torpedo flood values above 100% are normal: in battle the base chance is scaled down by the target's torpedo protection (the Torp Reduction stat on its Survivability card) and any flood-resistance modifiers, so a value above 100% keeps flooding likely even through partial protection. Not shown on the in-game port screen.
355%
Torpedo launcher traverse25 °/s
Launch arcs134° per side
Torp Turn
ƒTime to rotate the launchers 180 deg: tturn=180°25°/s=7.2s.
7.2 s
Torp Arming218 m
Per-side salvo damage
ƒOne side firing, all torpedoes hitting: per-side tubes x per-torpedo simulated damage = 4 x 19,567 = 78,268.
78,268
AA Defense
AA mount points54
Maximum AA range
ƒLongest-reaching family on the in-game AA card. Base AirDefense aura max range is 3.1 km; dual-purpose mount auras extend it.
5 km
25 mm/60 Type96 mod. 118×1 25mm
25 mm Type96 mod. 124×2 25mm
25 mm Type96 mod. 212×3 25mm
100 mm Type98 (DP)
ƒDual-purpose: your secondaries doing double duty against aircraft. The same mounts appear on the Secondary Battery card - shared guns, not extra hardware.
8×2 100mm
Far aura
Guns100 mm Type98 (DP)
Continuous DPS
ƒEffective DPS in in-game units (raw aura damage × 3.5 × hit probability, summed per contributing aura) - matches the Close-range AA DPS headline's currency. Includes 147 from dual-purpose secondaries firing as AA in this range band.
147
Range5 km
Near aura
Guns25 mm Type96 mod. 1 + 25 mm Type96 mod. 2 + 25 mm/60 Type96 mod. 1
Continuous DPS
ƒEffective DPS: 129 raw aura damage × 3.5 × 0.85 hit probability = 384 - the same in-game units as the Close-range AA DPS headline.
384
Range3.1 km
Total DPS in Aura
ƒFar 147 + Near 384 = 531
531
Flak bursts
Bursts
ƒEach ~2 s wave fires 2 quick salvos of 4 clouds ahead of the attacking squadron, plus 2 stray clouds farther out that appear off-beat between waves - up to 10 clouds per wave × 230 damage each. Planes that fly into a cloud take its damage; clouds dissipate before the next wave lands. Defensive AA Fire, where fitted, multiplies the salvo repeats within each wave.
2 salvos × 4 clouds + 2 outer
Cloud damage
ƒDamage a plane takes for flying into one flak cloud, before any reductions.
230
Cloud spawn chance
ƒEach cloud in the pattern rolls this chance to spawn, so waves average fewer clouds than the maximum. Often called flak 'hit chance', but spawned clouds always damage planes that fly into them - the roll is on spawning.
75%
Wave rate
ƒA flak wave spawns roughly every 2 s - timed frame-by-frame from gameplay footage and consistent across ships.
every ~2 s
Fired by
ƒFlak keeps firing while at least one secondary battery mount is operational - even losing every other AA mount does not stop it.
Secondary battery
Flak zone
ƒThe activation band: flak fires while attacking planes are inside it. Clouds are placed ahead of the planes' path, so bursts can land short of 2.5 km or past 5 km - once planes get inside the band, new waves stop. AA range bonuses push the outer edge out; the 2.5 km inner edge does not move.
2.5-5 km
S
Secondary Battery
Mounts11
Firing range6.0 km
Shell Grouping (σ)1
Secondary dispersion type
ƒMax dispersion = range (km) × 57 + 30. Each dispersion type sets its own slope; this is not a percentage applied to a standard baseline.
Standard
Max secondary dispersion @ 6 km
ƒ6 km × 57 + 30 = 372 m.
372 m
100 mm Type98 (×8) (DP)
ƒDual-purpose: the same mounts also fire at aircraft, so they appear on the AA Defense card too - shared guns, not extra hardware.
Caliber100 mm
Reload time3 s
HE Damage1,700
Muzzle Velocity1000 m/s
Fire Chance6%
Armor Pen17 mm
Show 1 more gun family
155 mm 3rd Year Type (×3)
Caliber155 mm
Reload time12 s
HE Damage2,600
Muzzle Velocity925 m/s
Fire Chance10%
Armor Pen26 mm
Maneuverability
Engine power145,000 hp
Maximum speed28.2 kt
Turning circle radius880 m
Rudder shift time17.2 s
Engine power-boost threshold7 kt
Engine spool-up time23 s
Reverse spool-up time11.5 s
Reverse speed
ƒtop speed / 4 + 4.9 = 28.2 / 4 + 4.9 = 12 kt. The community reverse-speed model from the WoWs ShipBuilder project, the same source as the acceleration model on this card. Base value; speed modifiers scale it. Not shown on the in-game card.
12 kt
Crash stop
ƒSeconds from top speed to a dead stop after ordering full reverse: reverse power winds in over the reverse spool-up while water drag does most of the braking. Same community-model simulation as the acceleration times, using the ship's own reverse-power ratio from in-game data. The full curve is on the acceleration chart.
37 s
Engine boost threshold (reverse)
ƒSpeed below which the engine's built-in power boost applies in reverse. Matches the in-game maneuverability card's reverse threshold (Vampire II reads 10.5 here and the card shows 11; the card rounds half up).
9 kt
Acceleration 0-90%
ƒTime to reach 90% of top speed (25.4 kt of 28.2 kt), from our in-house acceleration model.
36.5 s
Acceleration 0-99%
ƒTime to reach 99% of top speed (27.9 kt of 28.2 kt). 99% rather than 100% because true top speed is asymptotic (thrust meets drag), so the last fraction of a knot is never quite gained.
59.1 s
Traverse-to-turn ratio
ƒHow many degrees the turret can swing for each degree the hull turns. Turn rate ωhull=180π·Vmax(m/s)Rturn=180π·28.2·0.5144880=0.94°/s, so ratio=ωturretωhull=5.140.94=5.4×. Below 5 the turrets drag in a turning fight; 25+ keeps up with any rudder.
5.4× slow
Concealment
Detectability by sea15.84 km
Detectability by air12.67 km
Smoke firing penalty15.4 km
Detect when firing (sea)
ƒEqual to the ship's main battery range (never below base detectability): firing makes you visible to everyone you can reach. Matches the in-game 'Detect Firing Sea' value on all 8 unmodified captures, and range-modified captures track the modified range.
17.18 km
Detect when firing (air)
ƒAir detectability plus the gun-firing bloom (8.2 km, which tracks main-battery caliber x 0.020). Matches the in-game 'Detect Firing Air' value on every captured ship.
20.87 km
Detect when on fire (sea)
ƒBase sea detectability + 2.0 km while burning; matches the in-game 'Detect Fire Sea' value on every captured ship.
17.84 km
Detect when on fire (air)
ƒBase air detectability + 3.0 km while burning; matches the in-game 'Detect Fire Air' value on every captured ship.
15.67 km
Guaranteed Detect2 km
Consumables
Damage Control Party∞ charges · 80 s reload · 10 s active
Repair Party3 charges · 80 s reload · 28 s active · 11,298 HP (14% of max HP) total heal (per charge)
ƒHeal per second (0.5%) x effective active time (28 s) = up to 14% of max HP restored per charge.
· 33,894 HP (42% of max HP) total heal (all charges)
ƒ14% per charge x 3 charges = up to 42% of max HP if the whole Repair Party loadout is used.
· 404 HP/s (0.5% of max HP) heal per second
ƒ0.5% of max HP (80,700 HP) per second = 404 HP/s. WoWS heals a flat percent of MAX HP each second, so this rate holds at any health level.
Secondary Battery Booster3 charges · 160 s reload · 30 s active · +100% grouping · -50% dispersion

See all derived stats

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All values are ship base stats with modifications and upgrade changes denoted inline.

Numbers the spec table cannot show directly: alpha-strike math, DPM, dispersion, AP penetration. Click the formula chip on any row to reveal how it is calculated.

Main battery formulas

Shell Grouping (σ)1.9
Max Horiz Disp207.7 m at 17.2 km
Horizontal dispersion ellipse width at max range, from the verified WoWS dispersion model: σH=(R30·idealRadiusminRadiusidealDistance+minRadius)·30 =(1717730·102.81000+2.8)·30=207.7m
Shell scatter width @ 5 km120 m
Horizontal scatter at a fixed 5 km, from the same verified dispersion model as the rows below - a knife-fight-range anchor comparable across ships.
Shell scatter width @ 10 km156 m
How wide your shells scatter at 10 km, from the same dispersion model as the max-range figure above. Picking a fixed range makes this number directly comparable from ship to ship: max-range dispersion makes a longer-range gun look worse even when it's tighter at any common range. The interactive Dispersion tab on the Charts card plots the full curve from 0 to max range.
Shell scatter width @ 15 km192 m
Horizontal scatter at a fixed 15 km, from the same verified dispersion model - the long-range anchor. Only shown when the ship's guns reach 15 km.
Max Vert Disp166.1 m at 17.2 km
Vertical dispersion ellipse height at max range: σV=σH·radiusOnMax =207.7·0.8=166.1m
Shell scatter height @ 10 km98.7 m
How tall the same scatter ellipse is at 10 km. Comparable from ship to ship for the same reason as the width value above. The height/width ratio is a piecewise-linear curve through three points from the ship's own dispersion data: radiusOnZero=0.2 at 0 m, radiusOnDelim=0.6 at delim·Rmax=0.5·17177=8588 m, and radiusOnMax=0.8 at 17177 m. Above the kink: k=0.6+(0.80.6)·100008588171778588=0.6329, so σV=σH·k=156·0.6329=98.7m.
Med Horiz Disp65.6 m at 17.2 km
50%-hit horizontal radius: σH,50=σH·0.6σ =207.7·0.61.9=65.6m
Med Vert Disp52.5 m at 17.2 km
50%-hit vertical radius: σV,50=σV·0.6σ =166.1·0.61.9=52.5m
AP Pen Close880.5 mm point-blank
Canonical community AP formula (jcw780/wows_shell), evaluated at muzzle velocity: P=107·K·m0.69·d1.07·v01.38 =107·2650·10200.69·0.411.07·8341.38=880.5mm. Matches the in-game spec card.
AP Pen Far486 mm at 17.2 km
Same formula at the ship's max firing range (17.2 km), where the shell has slowed to 542.2 m/s: P=107·2650·10200.69·0.411.07·542.21.38=486mm.
AP pen 5 km731 mm
AP penetration at a fixed 5 km, read off the same PC-validated ballistic curve as AP Pen Close/Far: the shell's impact velocity at that range fed through the canonical community AP formula P=107·K·m0.69·d1.07·v1.38. Fixed anchors make ships directly comparable at the same fighting distance; the Charts card plots the full curve.
AP pen 10 km611 mm
AP penetration at a fixed 10 km, read off the same PC-validated ballistic curve as AP Pen Close/Far: the shell's impact velocity at that range fed through the canonical community AP formula P=107·K·m0.69·d1.07·v1.38. Fixed anchors make ships directly comparable at the same fighting distance; the Charts card plots the full curve.
AP pen 15 km519 mm
AP penetration at a fixed 15 km, read off the same PC-validated ballistic curve as AP Pen Close/Far: the shell's impact velocity at that range fed through the canonical community AP formula P=107·K·m0.69·d1.07·v1.38. Fixed anchors make ships directly comparable at the same fighting distance; the Charts card plots the full curve.
HE flight time @ 10 km4.98 s
How long an HE shell takes to reach a target at a fixed 10 km, from the same numerically integrated trajectory the Charts card plots. The shell slows under quadratic air drag, adrag=kρv2, where ρ is air density from a standard-atmosphere profile and k bundles the shell's drag coefficient, caliber and mass: k=πCdd28m=π·0.34·0.4128·1016=2.21×105. That runs from a 834 m/s muzzle velocity in 0.02 s steps under gravity 9.8 m/s² until the shell lands, then divides by 2.77: the game clock runs faster than real time, and that factor was measured against stopwatch runs in the Training Room. Lower is better, since a faster shell is harder to dodge and needs less lead.
AP flight time @ 10 km4.98 s
How long an AP shell takes to reach a target at a fixed 10 km, from the same numerically integrated trajectory the Charts card plots. The shell slows under quadratic air drag, adrag=kρv2, where ρ is air density from a standard-atmosphere profile and k bundles the shell's drag coefficient, caliber and mass: k=πCdd28m=π·0.34·0.4128·1020=2.2×105. That runs from a 834 m/s muzzle velocity in 0.02 s steps under gravity 9.8 m/s² until the shell lands, then divides by 2.77: the game clock runs faster than real time, and that factor was measured against stopwatch runs in the Training Room. Lower is better, since a faster shell is harder to dodge and needs less lead.
HE penetration68 mm
68 mm ≈ 410 mm caliber / 6 (standard HE penetration ratio).
AP overmatch28 mm
floor(410 mm caliber / 14.3) = 28 mm (AP auto-penetrates plating this thick or less).
AP AOE Radius250
AP shell over-penetration splash radius; scales with shell mass. Wickes 102mm = 3, standard 152mm CL ~ 20, Iowa 406mm ~ 270, Yamato 460mm = 400, Incomparable 650mm = 550 (max). Larger value = bigger splash damage area when AP over-pens.
Broadside guns used for alpha8
All 8 barrels bear on the broadside.
Turret turn time35 s
180 degrees / 5.14 deg/s traverse speed = 35 s.
HE full-salvo alpha52,000
6,500 HE damage x 8 broadside guns = 52,000.
AP full-salvo alpha108,800
13,600 AP damage x 8 broadside guns = 108,800.
HE DPMInitial: 124,800 → 138,667
Zero upgrades: 52,000 HE full-salvo alpha x 60 / 25 s base reload = 124,800. All upgrades (Main Battery Mod. 3 = -10% reload): 52,000 HE full-salvo alpha x 60 / 22.5 s all-upgrades reload = 138,667.
AP DPMInitial: 261,120 → 290,133
Zero upgrades: 108,800 AP full-salvo alpha x 60 / 25 s base reload = 261,120. All upgrades (Main Battery Mod. 3 = -10% reload): 108,800 AP full-salvo alpha x 60 / 22.5 s all-upgrades reload = 290,133.
Shells/minInitial: 19.2 → 21.3
Zero upgrades: 8 broadside guns x 60 / 25 s base reload = 19.2. All upgrades (Main Battery Mod. 3 = -10% reload): 8 broadside guns x 60 / 22.5 s all-upgrades reload = 21.3.
Fires/minInitial: 5.76 → 6.4
Zero upgrades: 19.2 shells/min x 30% fire chance = 5.76. All upgrades (Main Battery Mod. 3 = -10% reload): 21.3 shells/min x 30% fire chance = 6.4.

Torpedoes

Torpedo detectability2.2 km
Estimated torpedo reaction time11.7 s
detectability / (speed kt x 2.6855 game-speed factor, m/s per knot, calibrated from in-game measurement; the community's traditional 2.6 reads about 3% slower).
Torpedo speed70 kt
Travel time to max range79.8 s
range / (speed kt x 2.6855 game-speed factor, m/s per knot, calibrated from in-game measurement).
Torpedo module damage1,400
Per-torpedo module/blast damage parameter from in-game data. Most torpedoes carry 500 to 2,000; ships announced by WG as dealing increased module damage carry 9,000 to 12,000, so their hits knock out engines, rudders, and turrets far more often. Comparative figure; the exact module-HP conversion is not published.
Tube count8
2 launchers x 4 tubes.
Per-side salvo4 torpedoes
tube count / 2 (symmetric port/starboard launcher layout; common on cruisers and battleships with deck torpedoes).
Full-salvo damage156,536
All tubes hitting one target: tubes x per-torpedo simulated damage = 8 x 19,567 = 156,536.
Per-side salvo damage78,268
One side firing, all torpedoes hitting: per-side tubes x per-torpedo simulated damage = 4 x 19,567 = 78,268.

AA defense

AA DPS at max range147
Only families that reach 5 km contribute at the outer edge of the AA bubble. In-game families: 25mm Type96 single 18x1 -> 128 DPS @ 3.1 km; 25mm Type96 double 24x2 -> 171 DPS @ 3.1 km; 25mm Type96 Triple closed 12x3 -> 85 DPS @ 3.1 km; 100mm65 Type98 8x2 -> 147 DPS @ 5 km.
Maximum AA range5 km
Longest-reaching family on the in-game AA card. Base AirDefense aura max range is 3.1 km; dual-purpose mount auras extend it.
AA DPS layered by range147 DPS @ 5 km, 531 DPS @ 3.1 km
Cumulative AA DPS at each family range threshold. Inner ranges stack the outer families, so a target closing the distance hits stronger AA bubbles as it crosses each band.
AA DPS at point-blank531
Sum of every family's average DPS, achievable only inside the closest-range family (3.1 km).
AA threat index1925
SUM over AA auras of (aura DPS x aura range km). A plane crossing the AA bubble is exposed to each aura for a time proportional to that aura's range, so long-reach DPS is worth more than the same DPS in a short bubble. Units: DPS*km; used to rank overall AA threat across the cohort.
Near aura range3.1 km

Secondary battery dispersion

Secondary dispersion typeStandard
Max dispersion = range (km) × 57 + 30. Each dispersion type sets its own slope; this is not a percentage applied to a standard baseline.
Max secondary dispersion @ 6 km372 m
6 km × 57 + 30 = 372 m.
Secondary dispersion @ 5 km315 m
Same per-type line evaluated at a fixed 5 km: 5 km × 57 + 30 = 315 m.

Secondary battery firepower

Secondary DPM (per side)330,500
Sum across all secondary families of (per-side barrels × 60 / reload_s × alpha), where per-side barrels = mounts × barrels-per-mount / 2 (the guns that bear on one broadside target). Per-family: 8×2 100 mm (8/side) × 60/3 × 1700 = 272,000 + 3×3 155 mm (4.5/side) × 60/12 × 2600 = 58,500. Assumes every shell hits (real hit rate is lower; the Brawl matchup tool on the Compare page folds in dispersion + target armor).
Max HE alpha2600
Maximum HE damage per shell across secondary HE families. Best on this ship: 2600 from the 155 mm family.
Max HE fire chance10%
Maximum per-shell fire chance across secondary HE families (before target fire resistance is applied). Best on this ship: 10% from the 155 mm family.
Max HE pen26 mm
Maximum HE armor penetration across secondary HE families (caliber × 1/6 for most nations; 1/4 for German/UK BBs). Shells whose pen falls under a plate's armor thickness shatter for 0 hull damage though fire chance still applies. Best on this ship: 26 mm from the 155 mm family.

Armor Beta

Hull HP 80,700, distributed across 5 hull zones, each with its own plate thicknesses, saturation cap, and pen thresholds. HP caps are the exact in-game values, not estimated.

Bow & stern32 mm

Overmatched by 7 AP guns here: Incomparable SE 25IncomparableYamato and 4 more. Angling still helps against the rest.

Belt / citadel356 mm

Citadels come from a flat broadside at close range; held past ~30° of angle, AP shatters or bounces.

Farming19 mm

Superstructure and extremities take HE pens and AP overpens from nearly any gun: steady chip damage. Fire resistance 40%, fires burn 60s. Range-by-range in the Compare tool →

Section Plates HP cap Threats Tactic
Bow32 mm primary (range 32–360 mm)3,800 (5% of HP)
Overmatched by 460mm+ AP (Aki, Musashi)Angle bounces 410mm32 mm: HE pens from 203mm+
Bow-tank fits behind this exterior plate. Saturation is FAST here; the cap is often only a few thousand HP.
Hull (midship)360 mm primary (range 45–380 mm)60,500 (75% of HP)
No common AP caliber overmatches360 mm: no common HE pens
Largest HP pool. Citadel sits behind these plates; thinner deck and side plating absorb the rest.
Stern32 mm primary (range 32–356 mm)3,700 (5% of HP)
Overmatched by 460mm+ AP (Aki, Musashi)Angle bounces 410mm32 mm: HE pens from 203mm+
Mirror of bow. Same fast saturation.
Citadel356 mm primary (range 38–360 mm)≈ 165,500 (effectively no cap)
Citadel pen: full damageOver-pen: ×0.10 damage
Effectively no cap; citadel pool sits at ~165k HP on every ship. An AP citadel penetration deals the shell's full damage, the biggest single hit available; only over-penetrations are damped, to ×0.10.
Superstructure19 mm primary (range 19–410 mm)3,500 (4% of HP)
Any HE ≥16 mm pens at full damage
Any HE ≥16 mm pens at full damage. HE-spam target, and the section saturates fast (often only a few thousand HP).
Turret (module, per magazine)separate HP pool, does not drain ship HP40,400 magazine HPTurret knocked outPer-turret powder-magazine HP, a separate pool that does not drain ship HP. As it is worn down the turret is likelier to be knocked out, and a smaller pool gets there faster.
Secondary mount (155 mm mount)separate HP pool, does not drain ship HP800 per-mount HPDestroyed at 0 HPPer-mount HP for the heaviest secondary on this ship. A mount destroyed at 0 HP is out for the rest of the battle; DCP does not repair destroyed mounts. Smaller (lighter-caliber) secondaries typically share the same HP value.
AA mount (25 mm mount)separate HP pool, does not drain ship HP200 per-mount HPDestroyed at 0 HPPer-mount HP for the heaviest AA on this ship. An AA mount destroyed at 0 HP stops shooting down planes for the rest of the battle; DCP does not repair destroyed mounts. HE shells specifically target AA mounts since the small-caliber HP pool falls fast.
Rudder (module)separate HP pool, does not drain ship HP24,200 module HPIncapacitated at 0 HPWhen module HP reaches 0 the rudder locks at its current angle until DCP repairs it. Repair via Damage Control Party.

Saturation cap = HP a section can absorb before further damage to it is reduced (the "bow-tank" effect). Citadel pool is ~165k on every ship (effectively no cap); damage is gated by pen/over-pen multipliers instead. Superstructure saturates fast but HE always pens regardless of the plate thickness. Rudder (and other module HPs) are a separate pool from ship HP: damaging a module doesn't drain ship HP. Incapacitated modules like the rudder and engine are restored by DCP, but secondary and AA mounts destroyed at 0 HP stay out for the rest of the battle.

Open in Charting Tool

Ship Charts

Balance History

Balance updates affecting Iwami. Cards are condensed; use each source link for full context.

Buff ×3Main Battery ×1Torpedo ×1
2024-12-12

Ministry of Balance: Breaking the Ice

  • We're aiming to boost the performance of the Iwami duo with extra damage output and better torpedoes.
  • Main battery AP shell maximum damage increased from 12,750 to 13,600.
  • Torpedo speed increased from 67 to 70 knots.
Read the full official post
Exteriors

Skins & permanent camouflages

Every custom exterior Iwami can equip, from in-game data.

  • Iwami default exterior
    DefaultThe ship’s standard exterior

Primary official WG sources

Filtered to official World of Warships: Legends pages where this ship is a focus, reward, line member, or high-context variant mention.