Nether Portal Calculator
Convert Overworld and Nether coordinates, count obsidian, check which portals link, and plan Nether shortcuts.
Two portals link when the game finds the second one near the matching spot: within 16 blocks on the Nether side and 128 blocks on the Overworld side (Java 1.16+; Bedrock is very similar). Enter every portal you have and see where each one really leads — the usual reason a portal "goes to the wrong place".
Overworld portals
Nether portals
Where each portal leads
Tip: paste an F3 + C line into either pair.
More Minecraft tools: End Portal Finder · Stack Calculator · Circle Generator
Free Nether portal calculator for Minecraft
Convert Overworld and Nether coordinates, count obsidian, and find out why a portal goes to the wrong place.
Four tools in one: a coordinate converter that rounds like the game, an obsidian counter for any frame, a linking checker that follows the game’s own portal search, and a travel planner for Nether highways. Jump to how to use it, how linking works or the FAQ.
How to use the
Nether calculator.
Every tab has a Sample button, so you can try it before entering your own numbers.
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Step 01 / 05Convert coordinates
In Calculate Coordinates choose the direction, then type X, Y and Z — or paste F3 + C, and the tool detects which dimension you are in.
- →Rounded down like the game (Z −4 → Nether −1)
- →Shows which Overworld blocks land on the same Nether block
- →A ready /execute … tp command
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Step 02 / 05Count the obsidian
In Calculate blocks enter the frame size (4 × 5 up to 23 × 23) and choose with or without corners. You get the obsidian, the opening, the portal blocks and the lava buckets.
- →A drawing of the frame, with optional corners dashed
- →Common sizes in one click
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Step 03 / 05Check portal links
In Portal linking enter all your Overworld and Nether portals. The tool shows where each one really leads, marks one-way links, and gives the exact spot to fix them.
- →“Linked both ways” in green, problems in red
- →Paste F3 + C into a row to fill it
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Step 04 / 05Plan the trip
In Travel planner enter where you start and where you want to go. See the distance normally and through the Nether, the time saved, and where to build both portals.
- →Walking, sprinting and ice-boat times
- →Warns when two points are close enough to share a portal
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Share and download
Each tab can save or send its result:
- →Share link — every tab, value and portal in one link
- →Copy — the result as text for chat
- →Download TXT — coordinates, obsidian or travel plan as a file
- →⇄ Use result as input — convert back the other way
How much obsidian
a portal needs.
The frame’s outside size, with the corners left out (they are optional). Add 4 if you want corners.
How Nether portals
link together.
When you step through a portal, the game looks for a portal near the matching spot on the other side (Java 1.16+; Bedrock is very similar).
Divide or multiply by 8
X and Z are divided by 8 into the Nether and multiplied by 8 back. Y stays the same.
16 blocks in the Nether
Going into the Nether, the game searches for a portal within 16 blocks of the matching spot.
128 blocks in the Overworld
Coming back, it searches 128 blocks around the spot — that is why nearby Overworld portals get mixed up.
Closest wins
If several portals are in range, the nearest one in 3D (including height) is used. With none in range, a new portal is built.
Rule of thumb: build each Nether portal exactly at the coordinates the calculator gives, and keep Overworld portals that should stay separate more than 128 blocks apart.
5 Nether portal
tips.
Fix wrong links and build faster travel networks.
Questions
people ask.
Divide X and Z by 8 and round down; Y stays the same. Overworld 1000, 70, −250 becomes Nether 125, 70, −32. The calculator does it both ways and also reads F3 + C pastes.