Materials
In standard Java and Bedrock, you need:
- regular obsidian, not crying obsidian;
- a flint and steel or a fire charge to light it;
- enough to hold out on the other side: food, tools, solid blocks.
The minimum frame is four blocks wide and five blocks high, with a two-by-three opening in the middle. The four corners are optional: ten blocks of obsidian are enough. A frame can also be bigger, up to 23 × 23 blocks (Nether portal, Minecraft Wiki).
Steps
- Pick an open spot and place the two bottom blocks.
- Build up both sides, three blocks each.
- Close the top with two blocks, leaving the two-by-three opening.
- Light the inside with the flint and steel. A purple veil confirms the portal is active.
- Write down your coordinates before going through.
On the other side
Secure the area around the portal as soon as you arrive and note the new coordinates. The Nether is deceptive: one block travelled there equals eight blocks in the Overworld. It's a shortcut, but also a great way to get lost.
Two classic traps:
- water can't be placed normally in the Nether;
- sleeping in a bed there causes an explosion.
If the portal won't light
Check the material, the shape and the size of the opening. A single block of crying obsidian or a misaligned block is enough to stop it. Some servers disable a dimension: in that case, even a perfect frame will stay unlit.
Always bring a spare flint and steel: honestly, it's the item people most regret forgetting. And keep your written landmarks before the first detour.
Sources
Official Minecraft guide to obsidian, Nether portal, Minecraft Wiki. Sources checked in October 2026. Modded worlds and servers may apply different rules.