Rust Damage Calculator

• Damage per hit = weapon damage × ammo × muzzle attachment × hit-area multiplier × (1 − protection).
• Protection from every item covering the hit area is added together, then applied once, never above 100%. A hoodie (20%) under a metal chest plate (25%) stops 45% of a chest hit.
• Each Metal Armor Insert adds about 4% to the item it's in; crafted armour can have up to 3 insert slots.
• Shots to kill = health ÷ damage per hit, rounded up. Time to kill counts the gap between shots at the weapon's fire rate, plus a reload whenever the magazine runs out.
• A shotgun's figures assume every pellet hits the same place - at range many will miss.

Limits

• Close range only: damage falls off past about 20 m for rifles and 10 m for pistols, and Facepunch doesn't publish how far it drops.
• The 0.5 multiplier for legs, hands and feet comes from one community guide (another says 0.7 for the upper arm and thigh). Treat limb results as rough.
• Which hit areas each piece covers beyond its slot (does a chest piece cover the arms and stomach?) isn't published. Here chest armour protects chest hits only.
• Incendiary ammo's extra damage is counted as bullet damage; some of it may be fire that armour doesn't stop.
• Players usually go down wounded rather than dying outright; this counts damage to 0 health.
• Melee weapons, rockets and grenades are left out: their headshot and armour rules aren't published.

Confidence: medium for protection values, ammo and attachment multipliers (Facepunch's wiki) and for how protection stacks (Facepunch devblogs); low for limb multipliers, ballistic armour and inserts. Checked 2026-11-13. Sources: Facepunch Rust wiki - item protection tables; Facepunch Rust wiki - clothing slots; Facepunch Rust wiki - ammo pages; Facepunch Rust wiki - weapon mods; Facepunch - Devblog 105 (headshots and armour); Facepunch - Devblog 121 (armour stacking); Facepunch - Crafting Update (armour inserts, 2025-03-06); Rust Combat Log guide (fan tool - hit-area multipliers); rust.wiki weapon stats.