Rust Furnace / Smelting Calculator

Enter the amount of ore you want to smelt and see exactly how much wood you need, how long it takes, and what you get out.

Ore Amounts

Smelting Reference

OreOutputSmelt TimeWood Per UnitCharcoal Per Unit
Metal OreMetal Fragments5s2.51.88
Sulfur OreSulfur2.5s1.250.94
High Quality Metal OreHigh Quality Metal10s53.75

Furnace Comparison

FurnaceSmelt SlotsFuelNotes
Small Furnace1WoodCheapest to craft. Good for early game.
Large Furnace6Wood6x faster throughput. Needs to be placed on foundation.
Electric Furnace1Electricity (3 rWm)No wood needed. Quiet. Requires power setup.

FAQ

How long does it take to smelt metal ore in Rust?
Metal ore takes 5 seconds per unit in a small furnace. A stack of 1,000 metal ore takes about 83 minutes in a small furnace, or around 17 minutes split across a large furnace.
How much wood does a furnace use?
A small furnace burns 1 wood every 2 seconds (30 wood per minute). A large furnace burns at the same rate per slot but has multiple slots running simultaneously.
What is the charcoal ratio from smelting?
Every 1 wood burned in a furnace produces 0.75 charcoal. So smelting 1,000 wood gives you 750 charcoal, which is important for gunpowder crafting.
Is the electric furnace worth it?
The electric furnace smelts at the same speed as a small furnace but uses no wood. It requires 3 rWm of power. Great for saving wood but needs an electricity setup.