How a catch is rolled
The community's model of FISH!'s weight, price and bite maths, with the formulas shown. A model is not the game: the sell-price line is reported as developer-confirmed; the rest is reverse-engineered.
Model: WikiFish! Tool Database “Stats for Nerds”, read 2026-10-14. Used here with credit; the maths is restated, not copied.
Weight and Big Catch
Disputed — Huge and Tiny catches
This guide shows: Huge ×1.5 sell value; Tiny no value change.
Also reported: Huge multiplies the weight range ×4 and the value range ×2; Tiny forces the weight to 0 kg (WikiFish Tools appraisal model). WikiFish! Tool Database
What would settle it: A Huge and a Tiny catch of the same species, with the weight and sell price shown in game.
Reviewed 2026-10-14. All open questions
Base ranges are this guide's community-measured weight and sell ranges, read as the price at the lightest and heaviest weight. Your rod's Max Weight caps what you can land.
Bite wait and catches per hour
Wait = 14 s × (1 − Attraction ÷ 100), so every 5% is 0.7 s. Each cycle adds a 1.5 s cast delay. Reel times vary by fish and are not published, so enter your own.
Measure a fish's true range
For contributors: turn extreme catches into a fish's real limits.
True maximum
True minimum
Use a rod whose Max Weight is well above the fish, or you will be measuring the rod. The negative Big Catch version only works because the roll is capped at the top of the curve.
Luck scaling
The model: LuckMult = max(0.01, 1 + Luck ÷ 100), and each rarity's weight is multiplied by LuckMult ^ exponent. Negative exponents make common rarities rarer as Luck rises.
| Rarity | Exponent |
|---|---|
| Trash | -1 |
| Abundant | -1.2 |
| Ultimate Secret | 1.26 |
| Every other rarity — not published, so no odds are calculated here. | |