D4 Damage Calc

A static web app that helps you find the highest-leverage stat slots on your Diablo 4 Season 13 (Lord of Hatred) build.

It's a faithful port of Avarilyn's damage optimization spreadsheet, made interactive, mobile-friendly, and shareable via URL.

🔗 Live: https://jlian.github.io/d4-damage-calc/

Damage in D4 is a product of "buckets": additive damage, main stat, multiple [x] multiplier categories, weapon damage, skill ranks, etc. Each bucket has diminishing returns: the more it has, the less each new affix is worth.

This tool tells you which bucket is small and therefore which affix would give you the biggest gain per slot.

1. Pick your class (sets main stat divisor).
2. Strip your gear in-game and record your naked baseline main stat + additive total. (Hover each in-game additive stat and use the BOTTOM number, the top one lies.)
3. Enter your weapon damage, skill coefficient (level 1), and base crit chance.
4. Add each gear piece's affixes via the slot grid. Use the bucket dropdown so each affix lands in the right pool.
5. Optionally add standalone [x] aspects/uniques in the bottom card (Grandfather, Godslayer, etc.).
6. Look at the Buckets panel on the right. The top row (sorted by Weight) is your highest-leverage upgrade target.

The calculator persists state to your browser. The Copy Share Link button gives you a URL with all your inputs embedded, share with friends or save as a snapshot.

• Damage formulas, methodology, and design from Avarilyn:
  • DEEP DIVE: DAMAGE CALCULATION IN DIABLO 4 EXPLAINED WITH PROOF
  • DEEP DIVE: HOW TO OPTIMIZE YOUR DAMAGE IN DIABLO 4!
  • Original Google Sheets calculator

This tool is unofficial fan-made and not affiliated with Blizzard or Avarilyn. All math is theirs; this is just a different UI on top.

npm install
npm run dev    # dev server
npm run build  # static output to dist/

Pure client-side: Vite + TypeScript + Tailwind CSS. No backend. State lives in URL hash + localStorage. Deployed to GitHub Pages via Actions.

MIT