Building · Basics · 1.21
How to Make a Furnace
The furnace is the first machine almost everyone builds. It turns raw ore into ingots, sand into glass, and food into a meal, all for the price of eight cobblestone.
The recipe
Eight cobblestone around the edge of the crafting grid, centre left empty.
What it smelts
Drop an item in the top, fuel in the bottom. A few of the everyday jobs:
Plus every ore, raw food, clay, cactus and more. The full smelting list is on Astroworld crafting.
Fuels, ranked
The two upgrades
Blast furnace
Smelts ores and metal twice as fast. Add a furnace + iron + smooth stone.
Smoker
Cooks food twice as fast. Add a furnace + four logs.
Quick answers
Which blocks work in the recipe?
Eight cobblestone in a ring. Blackstone and cobbled deepslate also work; smooth stone does not.
What is the best fuel?
Coal and charcoal for everyday jobs (8 items each). Lava buckets (100) and blocks of coal (80) for big batches. Charcoal is renewable, smelt logs to make it.
How long does one item take?
About 10 seconds. One piece of coal smelts 8 items before it runs out.
Blast furnace or smoker?
A blast furnace smelts ores and metal twice as fast; a smoker cooks food twice as fast. Each only speeds up its own category.
Do furnaces give XP?
Yes. Collecting the finished items releases the experience the furnace banked while it worked.
Can I move a loaded furnace?
Mining it drops the furnace empty, so pull the contents and fuel out first.
Why won't iron and gold drop from the ore I smelt?
Iron and gold tools, armour and horse armour do not burn into ingots. They drop nuggets instead. Smelt raw iron, raw gold or the deepslate ore variants to get full ingots.
Does mining a furnace with Silk Touch keep it?
No tool enchant is needed. A furnace drops itself with any pickaxe. Mining with a fist or wrong tool still drops it, just slower, and the fuel and contents are lost if left inside.
How many items does one log smelt?
A single oak log or any plank set gives 1.5 items of smelting, so one log smelts one item with a little left over. Burn spare saplings, sticks (0.5 each) and crafting leftovers before wasting coal.
Can I make charcoal without coal?
Yes. Put any log in the top slot and burn a plank, stick or sapling under it. The log comes out as charcoal, which fuels the next batch. That bootstrap means you never need to find coal to start smelting.
What is the fastest way to smelt a full stack?
Run several furnaces in parallel rather than one. A blast furnace halves the time on ore and metal but not on food or stone, so keep a plain furnace for cobblestone, sand and clay.
Smelting tips and common mistakes
Small habits that save fuel and stop you losing items.
- Smelt a full stack at once. Fuel keeps burning between items, so a single piece of coal that has started a smelt does not waste its remaining 7 uses if you queue more in the top slot.
- Drop fuel before the input is empty. If the furnace finishes and you walk off, the next coal you add starts a fresh burn and the spare ticks from the last piece are lost.
- Use a hopper above for the input and one below for output to build an auto smelter. A side hopper feeds the fuel slot. This empties finished items so banked XP is collected when you take them from the chest.
- Charcoal and coal are interchangeable in every recipe, but only coal makes a block of coal. Keep coal for storage and torches, burn charcoal as fuel.
- A blast furnace and smoker each cost a normal furnace to craft, so build the plain furnace first. Iron, gold, copper and ancient debris go in the blast furnace; raw meat, fish, potatoes and kelp go in the smoker.
- Lava buckets smelt 100 items but the empty bucket is returned, so feed lava into a furnace with a hopper for hands-off bulk smelting.
The furnace pairs with almost everything. Grab the recipes for it and its upgrades on Astroworld crafting, look up coal, charcoal and iron on the items database, or keep your smelted goods tidy with a bundle.
Cobbled Deepslate
Smooth Stone
Lava Bucket
Blackstone
Deepslate