Nether Portal Calculator
Type the coordinates of a portal in either dimension and get the matching coordinates in the other, the exact area the game searches for an existing portal, and where a new portal would be placed.
How it works
The 1:8 ratio
Travelling one block in the Nether equals eight blocks in the Overworld. The game converts an Overworld position (X, Y, Z) into the Nether as (floor(X ÷ 8), Y, floor(Z ÷ 8)), and a Nether position back into the Overworld as (X × 8, Y, Z × 8). Y is never scaled.
Portal linking
When you step through a portal, the game converts your coordinates and looks for an existing portal near that target: within a 256×256 block square (128-block radius) in the Overworld, and within a 32×32 block square (16-block radius) in the Nether on Java 1.16.2 and newer. Java 1.16.1 and older, and Bedrock Edition, use a 128-block radius in both dimensions. Every height is searched, and the closest portal block by straight-line 3D distance wins.
If nothing is found, a new portal is generated within 16 blocks horizontally of the target (any height). When no valid spot exists it is forced at the target with Y clamped between 70 and 10 below the build limit. Because portals are only linked at the moment of travel, you can “steal” a link by building a new portal closer to the target than the old one.
Building a matched pair
- Note your Overworld portal position and divide X and Z by 8.
- Build the Nether portal at those coordinates (the calculator gives you a
/tpfor creative testing). - Check the “return trip” card: your Overworld portal should be inside the return search area, so both directions link to each other.
FAQ
How do I calculate Nether portal coordinates?
Divide your Overworld X and Z by 8 and round down (floor) to get the Nether coordinates; multiply Nether X and Z by 8 to go the other way. Y is not scaled. For example, an Overworld portal at X 1000, Z −500 corresponds to Nether X 125, Z −63.
Why does my portal link to the wrong portal?
When you enter a portal, the game converts your coordinates and searches a square area around the target — 128 blocks in the Overworld, 16 blocks in the Nether (Java 1.16.2+; 128 in both dimensions on Bedrock and old Java) — at every height, and links to the closest portal in 3D. If another portal sits closer to the target than the one you intended, it wins. Build the intended portal at the exact converted coordinates, and keep other portals well outside the search square.
Does the Y coordinate matter for Nether portals?
Y is not scaled, but it does count when the game picks the closest portal (3D distance including Y), so a portal at the same X/Z but 60 blocks higher can lose to a nearer one. If no portal is found, the new one is created within 16 blocks horizontally of the target; if it has to be forced, its Y is clamped between 70 and 10 below the build limit.
Is Nether portal maths the same on Bedrock Edition?
Yes — Bedrock uses the same 1:8 ratio, so the coordinate conversion is identical. The only difference is the search range for an existing portal: Bedrock searches 128 blocks in both the Overworld and the Nether, while Java (since 1.16.2) searches only 16 blocks in the Nether.
How far apart do portals need to be to not link to each other?
On Java, two Nether portals must be more than 16 blocks apart (in X or Z) from each other's targets so that only the intended one is inside the search square — that is more than 128 blocks apart in the Overworld. On Bedrock the Nether search is 128 blocks, so Nether portals need over 128 blocks of separation (1024 Overworld blocks) to be unambiguous.