Publisher notes · reviewed 29 October 2026
Nether portal linking is an 8:1 scale plus a search radius
Java Edition divides Overworld X and Z by eight, or multiplies Nether X and Z by eight, and copies Y. Integer division truncates toward zero, including for negative coordinates. After the conversion, the game reuses a portal if one already sits inside 16 blocks in the Nether or 128 blocks in the Overworld.
Why a nearby extra portal steals the link
The converted point is a search center, not a unique address. If another portal is already inside the destination radius, that portal is used. Fast-travel highways fail when a second base portal sits too close in the Nether. Delete or move the extra frame, or place the intended pair at the exact converted coordinates and light the destination first.
Y is not scaled. A portal at Overworld Y 80 still prefers Nether Y 80, which is often solid netherrack. Carve a room at that Y or accept that the game may create the return portal at a nearby air pocket and then fail to line up on the way back.
Worked examples
Overworld 800, 64, −1200
trunc(800/8) = 100 and trunc(−1200/8) = −150. The matching Nether point is 100, 64, −150. Flooring −150.0 is the same here; the difference appears on coordinates that do not divide evenly, such as −17 → −2, not −3.
Limits of this page
- Bedrock search and portal-spawn rules differ slightly; radii listed are Java Edition.
- Chunk loading, portal cooldown, and entity width are not modeled.