How to Make an Iron Farm in Minecraft

Iron is the workhorse material of Minecraft — tools, armour, rails, hoppers, anvils, beacons — and mining it vein by vein stops being fun around the third cave. An iron farm replaces all of that with one structure that manufactures iron while you build, explore or sleep. It runs on a piece of villager behaviour Mojang surely regrets: scared villagers summon iron golems.

The Mechanic in One Paragraph

In Java Edition, a group of at least three villagers who have slept recently and can see a threat — a zombie is the convenient option — will periodically call in an iron golem. If the zombie stays visible forever, the villagers never sleep and the system stalls, so good designs flash the zombie in and out of view. The golem spawns nearby, the farm kills it, and each golem drops 3–5 iron ingots (plus the occasional poppy). Your only jobs are keeping the zombie alive, contained and named.

What You Need

• 3 villagers and 1 zombie
• 3 beds
• Roughly 3 stacks of solid building blocks
• 2 sticky pistons and 2 sculk sensors (or a simple redstone clock instead)
• 1 water bucket, 1 lava bucket
• 4 signs, 1 hopper, 1 chest
• 1 name tag (so the zombie never despawns)
• Ladders or scaffolding to build with

Step 1: The Villager Chamber

Build a tower at least 12 blocks tall — distance from the ground matters, because you want golems to spawn in your farm and nowhere else. On top, make a platform of at least 7×7 with a two-block-high border. Place the three beds inside and get your three villagers up there by minecart or boat. Build the farm well away from any village (at least 64 blocks) so outside beds and golems cannot interfere.

Step 2: The Zombie Cage

In one corner of the chamber, box in a one-block cell for the zombie. The trick used here: two sticky pistons in the wall hold a solid block that slides back and forth in front of the zombie, and a sculk sensor on each piston listens to the villagers and zombie shuffling around, which keeps the pistons cycling. The villagers glimpse the zombie, panic, summon a golem — then the block covers it, they calm down, sleep at night, and the cycle repeats. Use the name tag on the zombie before you seal the cage; an unnamed zombie will eventually despawn and silently kill the whole farm.

Step 3: The Spawning and Killing Platform

Roof the chamber with a three-block-high walled platform of its own. This is where golems appear. Put a water source in one corner so the flow sweeps across the platform towards the opposite corner. In that corner, replace the floor block with a hopper feeding a chest, and hang a pool of lava above it using signs — signs hold lava up while letting items fall through the gaps. The sequence is automatic: golem spawns, water pushes it into the corner, lava burns it down, ingots drop through the hopper into your chest.

Getting the Cast Into Place

Villagers travel best by minecart on a temporary rail line, or by boat shoved along a path. The zombie is easier: it will happily chase you. Lead it at night (or from a cave) into its cage, stand somewhere it can see you, and box it in. Do the name tag step the moment it is caught — future you says thanks.

Notes and Troubleshooting

• No golems? Check the villagers can actually sleep at night (the zombie must be hidden for part of the cycle) and that no golem is already alive somewhere in range — one golem standing in a cave below will block all new spawns.
• Golems on the ground? Your platform is too low or there is spawnable ground too close. Raise the farm and slab or light the area underneath.
• Bedrock players: golem spawning works differently on Bedrock — it needs a real village of at least 10 villagers, 20 beds and workstations for everyone. Scale the village up rather than copying this three-villager design.

Leave the chunk loaded — go AFK nearby, or route your other projects around the farm — and the chest fills steadily. A few stacks of ingots per session is a reasonable expectation for this simple build, which is more iron than most players ever spend.