Nether Portal Calculator

How to use it

1. Choose which dimension your coordinates are from.
2. Enter X, Z and, if you like, Y. Press F3 in Java or turn on show coordinates in Bedrock to read them.
3. Read the converted coordinates and copy them.
4. Open Will two portals link? and enter a portal you already have to see if the game will use it.

How the conversion works

The Nether is scaled 1 to 8 against the Overworld on the horizontal axes. One block in the Nether covers eight in the Overworld. The calculation is only on X and Z, the Y coordinate does not change. Going from the Overworld to the Nether the game divides X and Z by 8 and rounds down. Going back it multiplies by 8.

So an Overworld point at X 1200, Z -800 is at X 150, Z -100 in the Nether. A Nether point at X 150, Z -100 is at X 1200, Z -800 in the Overworld. Because of the rounding, converting a point there and back can move it by up to 7 blocks.

Worked example: linking a base and a mine

Your base is at X 1200, Z -800 and you want a fast road to a village at X 2000, Z 400. In the Overworld that is a walk of 1,600 blocks in X and 1,200 in Z. Convert both ends: the base is at Nether X 150, Z -100 and the village at X 250, Z 50. Build a Nether portal at the first point and a second portal at the second point, and the two Nether spots are only 100 and 150 blocks apart, so you can walk between them in a couple of minutes.

Conversion table

Portal search range in Java and Bedrock

When you step through a portal the game converts your position and searches around that point for a portal that already exists. The search area is a square, not a circle. In Java Edition it is 128 blocks in each direction when you arrive in the Overworld and 16 blocks when you arrive in the Nether. In Bedrock Edition it is 128 blocks in both. If the game finds a portal, it takes the closest one. If it finds none, it builds a new one.

The Java Nether range was cut from 128 to 16 blocks in snapshot 20w28a because the Nether is scaled. A radius of 128 there would cover a 1,024 block area in the Overworld. The Will two portals link? box uses these numbers and measures the distance along the larger of the two axes, as the square search does.

Building portals that stay separate

The usual problem is two portals that you think of as different gates and the game sees as one. In Java, two Overworld portals within about 128 blocks can both land on the same Nether portal. To keep them apart, convert the exact place you want in the Nether, build the Nether portal there, and then build the Overworld portal at the converted position. Keep different Nether portals at least 33 blocks apart in Java, so that the 16 block search of one does not reach the other. In Bedrock keep them more than 128 blocks apart.

Portal sizes

A portal frame is made of obsidian. The smallest is 4 wide and 5 high on the outside, which gives an opening of 2 by 3. The largest is 23 by 23 on the outside. Corners are not required for the portal to work. Always check that there is nothing but air in the opening before you light it.

Common mistakes

• Dividing Y by 8. Only X and Z are scaled.
• Mixing up the direction. Divide when you go to the Nether and multiply when you come back.
• Reading coordinates of the wrong block. Use the coordinates of the portal, not of where you stand when you read them.
• Ignoring the nether roof. Building on top of the Nether ceiling is possible, but the portal must still be inside the world height.

Related tools

Planning a big build near your portals? The stack calculator turns block counts into stacks and chests, and the circle generator helps with round bases and walls.

Sources and notes

The 1 to 8 scale, rounding, search radii and portal sizes come from the Minecraft Wiki page on Nether portals, checked on 27 October 2026. Rules can change between versions, so check the wiki if your version is new. BlockShapes is not affiliated with Mojang or Microsoft.