Nether Coordinates Calculator
Horizontally the Nether is 8 times smaller than the Overworld: X and Z are divided by 8 and Y stays the same. Enter coordinates on either side and the calculator works out the other point.
When you step through a portal, the game looks for a Nether portal within 16 blocks of this point. Build the second portal closer than any other so the two link up.
Description
The Nether is linked to the Overworld at a 1:8 scale. One block walked in the Nether equals eight blocks in the Overworld, which is why players use portals as shortcuts between distant bases.
How coordinates convert. Going from the Overworld to the Nether, X and Z are divided by 8 and rounded down, so −1 stays −1 and −9 becomes −2. Going back, X and Z are multiplied by 8. The Y height stays the same both ways.
Why portals link to the wrong place. When you step through a portal, the game converts the coordinates and looks for an existing portal near the resulting point: within 16 blocks in the Nether and 128 blocks in the Overworld. If several portals qualify it picks the nearest one, and if there are none it builds a new one. That is how a player can come out of a neighbouring portal instead of the one you built.
How to build a linked portal. Stand in your Overworld portal, enter its coordinates into the calculator and build the Nether portal at the resulting point. If the game has already created a portal somewhere else, break it so it stops catching the trip.
The calculator works both ways: change the coordinates in either world and the other point updates straight away.
How do you link Nether portals in Minecraft?
Divide the X and Z of your Overworld portal by 8 and build the Nether portal at the resulting point, keeping the same Y where the Nether allows it. When you step through, the game looks for an existing portal within 16 blocks of the converted point in the Nether, or 128 blocks in the Overworld, and picks the nearest one. If another portal is closer, you come out of that one instead. The calculator above does the dividing and multiplying for you.
