How Nether coordinates work
Every block you travel in the Nether equals 8 blocks in the Overworld horizontally. To convert Overworld X and Z to the Nether, divide by 8. To convert Nether X and Z back, multiply by 8. The Y coordinate (height) is not scaled. This is why the Nether is used as a fast-travel network: a 1,000-block trip in the Overworld is only 125 blocks in the Nether.
How to link two Nether portals correctly
- Stand where you want your Overworld portal and press F3 (Java) or turn on "Show Coordinates" (Bedrock) to read your X, Y, Z.
- Type them into the Overworld boxes above. The calculator shows where the Nether portal must go.
- Build your Overworld portal and light it. Travel through.
- In the Nether, walk to the calculated coordinates and build the second portal there, then light it.
- If a portal takes you to the wrong place, it is because a different portal was closer. Break the wrong one and rebuild at the exact calculated position.
Portal size
A portal frame must be made of regular obsidian (crying obsidian does not work). The smallest frame is 4 blocks wide and 5 tall (a 2×3 opening; the corners are optional). The largest is 23×23 (a 21×21 opening). Light it with flint and steel or a fire charge.
Building on the Nether roof
The Nether has a bedrock ceiling at the top. Some players build highways above it because there are no mobs, but getting there relies on a glitch in Java Edition and may be disabled on servers. The calculator keeps suggested Nether heights inside the normal playable area.
Frequently asked questions
How do Nether coordinates work?
One block in the Nether equals eight blocks in the Overworld on the X and Z axes. Divide Overworld X and Z by 8 to get Nether coordinates. The Y coordinate is not scaled.
Why did my portal link to the wrong place?
When you go through a portal, the game looks for an existing portal near the target coordinates before creating a new one. If another portal is closer, you arrive there. Build your second portal at the exact calculated coordinates to fix it.
What is the smallest Nether portal?
An obsidian frame 4 blocks wide and 5 blocks tall, giving a 2×3 opening. The four corners are optional, so it needs at least 10 obsidian.
Is the ratio the same in Bedrock Edition?
Yes. Both Java and Bedrock use the 1:8 ratio between the Nether and the Overworld.