fruitdeeps

A damage-per-second calculator for Old School RuneScape that accounts for overkill, and solves for which setup is fastest at every point in a fight.

Live at https://fruitdeeps.app/

Why "overhit"

Most DPS calculators take an average damage per tick and divide the target's health by it. That overestimates, because the killing blow almost always deals more damage than the target had left and the excess is thrown away. The bigger your hits are relative to remaining health, the further the estimate drifts.

fruitdeeps works from the full damage distribution rather than its average, so wasted damage on the final hit is counted instead of assumed away. Concretely, getDist(hp) folds every outcome that would deal more than the remaining health into the exact-kill bucket.

How it works

Hit distributions — a trie over sorted hit combinations

A single attack can produce several hits, and the same combination can arrive in any order. HitFreqStore sorts each combination descending and stores it in a trie: an edge is a damage value, a root-to-node path is a combination, and the node at the end accumulates that combination's probability.

Sorting first is the point. Without it, [3,8,12], [12,3,8] and [8,12,3] occupy three separate paths and their probabilities are spread across branches that all describe the same outcome. With it, they collapse onto one path and the probability accumulates in one place.

Time to kill — dynamic programming over remaining health

Every setup has a damage distribution and an attack speed. TtkOptimization builds a table of expected time-to-kill, indexed by remaining health, from the bottom up:

T(0) = 0
T(h) = min over setups of [ expected time for that setup to finish from h ]

It starts at 1 health, works out which setup is fastest there, then counts upward — each step reusing every result already computed, since a setup's time from h depends on where its hits leave the target.

The output is not a single number. It is the fastest setup at every remaining health value, plus the time each one would take.

Why that matters

The best setup changes as the fight progresses. The highest-DPS option stops being correct near the end, because a big slow hit spends time on health the target no longer has. Anything that solves for one "best setup" across a whole kill is answering a different question — and gets the endgame wrong precisely when it matters most.

Status

No longer actively maintained. Other calculators have since caught up and in most cases surpassed it. It stays up because the approach still gets referenced, and because the source is a compact worked example of solving a stochastic race with per-action costs.

Running it locally

git clone https://github.com/mark-b5/fruitdeeps
cd fruitdeeps
npm install
npm run dev

Then open http://localhost:3000.

Updating game data

Item stats come from a community-maintained OSRS database on GitHub. NPC stats are scraped from the wiki. Both are refreshed with the Node and Python scripts in importstuff/.