Block Circle ToolsHow do Nether coordinates work?
One block in the Nether equals 8 blocks in the Overworld, but only for X and Z. To go to the Nether, divide X and Z by 8 and round down. To go from the Nether to the Overworld, multiply X and Z by 8. Y does not change. So Overworld 800, 64, -240 matches Nether 100, 64, -30.
Nether X = floor(Overworld X ÷ 8) · Nether Z = floor(Overworld Z ÷ 8)
Overworld X = Nether X × 8 · Overworld Z = Nether Z × 8
The nether portal calculator above uses this 1 to 8 rule, which comes from the Minecraft Wiki Nether Portal page. Floor means round down to the next whole number below. For negative numbers that means more negative, so -29.9 becomes -30. Find your own X, Y and Z on the debug screen (F3 on Java), or turn on "Show Coordinates" in the world settings on Bedrock.
How far does the game search for a portal?
In Java Edition, the game searches a square 128 blocks out from the converted point in the Overworld and 16 blocks out in the Nether. In Bedrock Edition it searches 128 blocks out in both. The search covers the full height of the world. If several portals are in range, the closest one wins.
| Arriving in | Java | Bedrock |
|---|---|---|
| Nether | 16 blocks (32 × 32 square) | 128 blocks (256 × 256 square) |
| Overworld | 128 blocks (256 × 256 square) | 128 blocks (256 × 256 square) |
Java cut the Nether search from 128 to 16 blocks in version 1.16.2, to match the 1 to 8 scale. The closest portal is picked by straight line distance, and Y counts. That is why a portal on a high cliff can lose to one at the same height that looks farther away. If nothing is in range, the game looks for open ground within 16 blocks of the point and builds a new 4 by 5 portal with corners.
How to link Nether portals step by step
- Stand in your Overworld portal and write down X, Y and Z.
- Type them into the tool above. Note the Nether coordinates.
- Go through and walk to those coordinates in the Nether. Keep the same Y if you can.
- Build and light a new portal there. Break the portal the game made for you, if it is far away.
- Use the link checker to make sure both portals fall inside each other's search area.
The safest plan is to build the Overworld portal first, then the Nether portal at the exact converted spot. Going the other way works too, but one Nether block covers 8 Overworld blocks, so a small error in the Nether turns into a big one above.
Nether portal size: smallest and biggest
The smallest frame is 4 blocks wide and 5 tall, with an opening of 2 by 3. It needs 10 obsidian, since the corners are optional. The largest frame is 23 by 23, with an opening of 21 by 21. The frame must stand upright, and fire must be the last block you place.
| Opening | Frame | No corners | With corners | Portal blocks |
|---|---|---|---|---|
| 2 × 3 | 4 × 5 | 10 | 14 | 6 |
| 3 × 3 | 5 × 5 | 12 | 16 | 9 |
| 4 × 4 | 6 × 6 | 16 | 20 | 16 |
| 5 × 5 | 7 × 7 | 20 | 24 | 25 |
| 10 × 10 | 12 × 12 | 40 | 44 | 100 |
| 21 × 21 | 23 × 23 | 84 | 88 | 441 |
The count is two times the opening width plus two times the opening height. Add 4 for the corners. Minecraft.net describes the smallest portal as a door shaped frame with two blocks on the top and bottom and three on each side. Portals that the game builds for you always have corners, so you can mine 4 spare obsidian from them. Crying obsidian does not work in a frame, as the Nether survival guide notes.
Good to know
- The Nether has a bedrock roof from Y = 123 to 127, so it is 128 blocks high. A high Overworld portal can lead to a forced portal lower down.
- Nether portals do not light in the End.
- A Nether portal wider than 18 blocks can link each end to a different Overworld portal, since the game only looks 16 blocks out when it builds a new one.
- You can make obsidian without a diamond pickaxe by pouring water on lava source blocks. See the Nether portals tutorial.
Related tools
FAQ
Why did my portal take me to the wrong place?
The game sends you to the closest portal inside the search area around your converted point, even one you did not mean to use. The distance counts Y too, so a portal far above or below can lose to one that looks farther away on the map. Build the second portal at the exact converted point to be safe.
Do I divide Y by 8?
No. Only X and Z change. Y stays the same in both directions. If no portal is found and the game has to force one in open space, the Minecraft Wiki says it keeps Y between 70 and 10 below the world height, which is 118 in the Nether.
How do negative coordinates convert?
The game rounds down, toward the more negative number. So X = -9 in the Overworld becomes -2 in the Nether, not -1. This tool uses the same rule.
How much obsidian does a Nether portal need?
At least 10 blocks. The smallest frame is 4 wide and 5 tall, and the four corners can be any block or empty. With corners you need 14. The largest frame is 23 by 23, which takes 84 obsidian without corners or 88 with them.
What is the smallest Nether portal?
The smallest working frame is 4 blocks wide and 5 blocks tall, with an opening 2 wide and 3 tall. Without corners it takes 10 obsidian. Any smaller frame will not light.
How long do I stand in a portal?
The Minecraft Wiki says 80 game ticks, which is 4 seconds, in survival mode, and 1 tick in creative mode. Step out before the swirl ends to stay where you are.
Does the nether portal calculator work for Bedrock?
The 1 to 8 rule is the same. The search area is not. Java looks 16 blocks out in the Nether and 128 in the Overworld. Bedrock looks 128 blocks out in both, so Bedrock portals are more likely to link to an old portal by mistake. Pick Bedrock in the calculator to see the bigger search area.