Gun Fit Bonuses

The fit bonuses detailed on this page are the hidden fit bonuses. For the visible fit bonuses, please check individual ship girl or equipment pages.

What is fit?

Fit is a hidden bonus or penalty that certain ship types/classes receive when equipped with guns of the correct caliber. All information on this page is sourced from the spreadsheet maintained by y7h65, Dewy, and SWDN.

Large Caliber Guns

Fit Bonus Table

Equipment	Gangut	Kongou-class	Bismarck Vittorio Veneto-class	Iowa	Richelieu	Warspite	Nelson	Colorado	Aviation Battleships	Ise-class Kai Ni	Fusou-class Base	Nagato-class	Nagato Kai Ni	Mutsu Kai Ni	Yamato-class	Notes
35.6cm 38cm Twin	+7	+7	+4	+4?	+4	+6	0	??	+4	+4?	+2	+2	+2?	+2?	0
38.1cm	+7	+7	+4	+4?	+4	+8	0	??	+4	+4?	+2	+2	+2?	+2?	0
30.5cm	+10	+7	+4	+4?	+4	+6	0	??	+4	+4?	+2	+2	+2?	+2?	0
38cm Quad	0	0	0?	0?	+4~5	??	??	??	0	0?	0?	0?	0?	0?	0
381mm	+1	-2	+1	-2?	-2	+1~2	0	??	+2	??	+2	+2	+2?	+2?	0
41cm	-7	-5	-5	-5	-5	+2	+3?	??	+2	+4?	+2	+2	+5	+5	0	Does not include 41cm Triple and Twin Kai Ni
41cm Twin Gun Mount Kai 2	??	??	??	??	??	??	??	??	??	+6	??	??	+5~6	+5~6	??
41cm Triple Gun Mount Kai 2	??	-5	??	??	??	??	??	??	??	+4?	??	??	+5	+5	0
16in Triple Gun Mount Mk.7	-3	-5	-5	0	-5	??	??	??	0	??	+2	+2	0	0	0
16in Triple Gun Mount Mk.7 + GFCS	??	-6~7?	-4?	-2 +5 (Married)	??	-2?	0	??	??	??	+2?	+2?	??	??	??
16inch Mk.I Triple Gun Mount	-9~10	-5	-4~5	??	-7	+5	0	??	0	??	+3	+3	??	??	??
16inch Mk.I Triple Gun Mount + AFCT Kai	??	-6	??	??	-14	??	??	??	??	??	??	??	+4	+4	??
16inch Mk.I Triple Gun Mount Kai + FCR Type 284	??	-3	??	??	-8	+3~4	??	??	??	??	??	??	??	??	??
Prototype 46cm Twin Gun Mount	-7	-7	-7	-7	-7	-8	??	??	-3	??	-3	-3	-2?	-2?	+3
46cm Triple Gun Mount	-18	-10	-10	-10	-10	-11	-2~+1?	??	-7 -11 (Fast+)	-7? -11? (Fast+)	-7	-7	-4	-4	+3
46cm Triple Gun Mount Kai	??	-10	??	??	??	??	??	??	-4?	??	??	??	-6?	-6?	+7
51cm	-	-	-	-	-	-	-	-	-	-	-	0	-5	-8	0

• The values in this table are accuracy bonuses/penalties.
• Question marks indicate values still being tested.
• Marriage reduces the fit penalties by 40%.
  • It does not affect fit bonuses unless where indicated.

Calculating Large Caliber Fit

The formula for fit bonuses is:
[math]\displaystyle{ \text{Fit Bonus}_\text{Ship} = \sum \text{Fit Bonus}_\text{Gun} \times \sqrt{\text{Number of Guns Equipped}} }[/math]

An example: Kongou having 2 35.6cm and 1 46cm.
Fit Bonus: (7 x √2) + (-10 x √1) = -0.1

Medium Caliber Guns

Equipment	Light Cruisers	Agano-class	Ooyodo	Heavy Cruisers	Mogami-class	Mogami-class	Suzuya Kai Ni Kumano Kai Ni	Zara-class	Seaplane Tenders	Notes
15.2cm Naval Gun	+4N	+4N	+4N	??	??	??	??	??
14cm Naval Gun	+4N	+4N	+4N	??	??	??	??	??
14cm Twin Gun Mount	??	??	??	??	??	??	??	-5N
14cm Twin Gun Mount Kai	??	??	??	??	??	??	??	-7N
15.2cm Twin Gun Mount (Kai)	+2	+5+2N	+2	??	??	??	??	-6N?
Bofors 15.2cm Twin Gun Mount Model 1930	+3	??	??	??	??	??	??	??
15.5cm Triple Gun Mount Kai (Main)	-2-2N	-2-2N	+2	??	+2	+5	??	??
20.3cm SKC34 20.3cm Twin Gun Mount	0	0	0	??	??	??	??	-8-10N
20.3cm (IJN Only)	??	??	??	+5+5N	+5+5N	+5+5N	+5+5N	??
203mm / 53 Twin Gun Mount	-2-2.5N	??	??	??	??	??	+1	??

• The values in this table are accuracy bonuses/penalties.
• Question marks indicate values still being tested.
• The N indicates the variable fit from having more than one gun equipped.
  • For example equipping two 15.2cm Twin Gun Mount gives a bonus of +9 (5+(2x2)).
• The 20.3cm IJN fit only applies to night battle.
  • The bonus is applies to both accuracy and evasion.
  • There is the possibility that the bonus is capped at +15%. This means there is no further bonus when using more than 2 guns.

Medium Caliber Guns Firepower Bonus

Gun	Fit Bonus	Notes
14cm Twin Gun Mount 15.2cm Twin Gun Mount 15.2cm Twin Gun Mount Kai	+2
14cm Naval Gun 15.2cm Naval Gun	+1	The 15.2cm is a secondary gun

Calculating Firepower Bonus

The formula for the firepower bonus is:
[math]\displaystyle{ \text{Fit bonus} = (2 \times \sqrt{\text{No of Twin Guns}}) + \sqrt{\text{No of Single Guns}} }[/math]

Example calculation: A light cruiser with 1 15.2cm Twin and 2 15.2cm Singles
Firepower bonus: (2 × √1) + √2 = 3.4

Italian Heavy Cruiser Fit Bonus Zara and Pola a further firepower fit bonus when equipped with the 203mm / 53 Twin Gun Mount. In addition to the flat +1 accuracy bonus, the firepower bonus is calculated using the following formula:

[math]\displaystyle{ \text{Italian Gun Fit Bonus} = \sqrt{\text{No of Guns}} }[/math]

This firepower bonus is pre-cap.

High-Angle Guns

Equipment	Light Cruisers	Yura Kai Ni	Mutsuki-class	Kamikaze-class	Notes
12.7cm Single High-angle Gun Mount (Late Model)	+4N	+4+10N	+5	??
12.7cm Twin High-Angle Mount (Late Model)	+2+2N	??	??	??

• The values in this table are accuracy bonuses/penalties.
• Question marks indicate values still being tested.
• The N indicates the variable fit from having more than one gun equipped.
  • For example equipping two 15.2cm Twin Gun Mount gives a bonus of +9 (5+(2x2)).
• Only the Late Model variants were tested.
  • It is unknown if the 12.7cm High-angle Gun Mount also gives the same bonus.