How to Make a Nether Portal in Minecraft (Size and Linking)

To make a Nether portal in Minecraft, build a rectangular obsidian frame at least 4 blocks wide and 5 blocks tall, then light the inside with flint and steel or a fire charge. The smallest frame needs only 10 obsidian, because the four corners are optional. To link two portals, divide your Overworld X and Z coordinates by 8 and build the Nether side at exactly that spot.

Last checked: November 9, 2026. Frame sizes, search distances and the 8:1 ratio come from the game code and dimension data in Java 26.3, the current release.

What size can a Nether portal be?

The frame must be obsidian. Crying obsidian and other blocks do not work. The game measures the open space inside the frame:

Any rectangle between those sizes works, and the frame can face north-south or east-west. Bigger portals look nice, but they work exactly like small ones.

How do you build a Nether portal step by step?

1. Collect 10 obsidian, or 14 for a full frame with corners. Mining obsidian needs a diamond or netherite pickaxe.
2. Place the bottom row: 2 obsidian side by side.
3. Add temporary corner blocks. Put a block of dirt or cobblestone at each end of the bottom row. Obsidian cannot be placed in midair, so these give the sides something to sit on.
4. Build the sides: stack 3 obsidian on top of each corner block.
5. Close the top: put another temporary block on top of each side, then place 2 obsidian between them. Break all four temporary blocks afterward, or use obsidian corners if you have 14.
6. Light it with flint and steel or a fire charge on the inside of the frame. The purple portal fills the opening.
7. Step in and wait. In survival you need to stand inside for 4 seconds (80 ticks, the default for the players_nether_portal_default_delay game rule). In creative it is instant.

Flint and steel is 1 iron ingot plus 1 flint. A fire charge is gunpowder, blaze powder and coal or charcoal, which makes 3.

How do you make a portal without a diamond pickaxe?

You can make obsidian where you need it instead of mining it. Obsidian forms when water flows onto a lava source block, so you can cast the frame in place:

1. Build a mold out of cheap blocks like dirt or cobblestone that holds the shape of one frame column.
2. Pour a lava bucket into each frame spot.
3. Pour water over it so the water flows onto the lava. Each lava source turns into obsidian.
4. Pick up the water, break the mold, and repeat for the other parts of the frame.

Ruined portals are the other shortcut. These broken portals appear all over the Overworld and the Nether, and their frames often just need a few more obsidian. Their chests are worth opening too: each chest has about a 46% chance of flint and steel, about a 46% chance of a fire charge, and about a 46% chance of some obsidian. Some of their frame blocks are crying obsidian, which does not work in a portal, so swap those for regular obsidian.

How do Nether coordinates work?

The Nether has a coordinate scale of 8 in the game's dimension data. One block traveled in the Nether equals 8 blocks in the Overworld, but only on the X and Z axes. Height is not scaled.

This is why the Nether is a fast-travel network. A 1,000-block trip in the Overworld is only 125 blocks in the Nether. The Nether portal calculator does the math for you in both directions.

How do you link two Nether portals?

When you walk through a portal, the game takes your position, converts it with the 8:1 rule, and searches for an existing portal near that spot:

If it finds one or more portals in range, it sends you to the closest. If it finds none, it builds a new portal near the target point, adding a small obsidian platform if there is no safe floor.

To make a clean link every time:

1. Note your Overworld portal coordinates. Press F3 and stand inside the portal.
2. Divide X and Z by 8. Use the calculator if the numbers are awkward.
3. Go to the Nether and travel to those exact coordinates.
4. Build a portal there yourself and light it.
5. Test it both ways. Go back to the Overworld, then return to the Nether and check that you land where you expect.

Why does my Nether portal go to the wrong place?

The two search distances are the usual cause. The Overworld search covers 128 blocks, while the Nether search covers only 16, so links are not always two-way:

• Two Overworld portals close together can both lead to the same Nether portal. Overworld portals less than about 128 blocks apart land within 16 blocks of each other in the Nether.
• A Nether portal that is slightly off can send you to an old Overworld portal up to 128 blocks away instead of the one you came from.
• An auto-generated portal might have been placed far from where you wanted because the game looked for free space nearby.

The fix is to build the second portal yourself at the exact converted coordinates, then break or move any older portal that is closer to the target point.

Tips for using Nether portals safely

• Carry flint and steel. Explosions, including ghast fireballs, can break the portal blocks, and you will need to relight it to get home.
• Write down both sets of coordinates. The calculator helps, but keeping a note is faster when you are lost.
• Light the area around Overworld portals. On any difficulty except Peaceful, Overworld portals can spawn zombified piglins.
• Make the Nether side safe. A portal the game builds for you can end up on a ledge over lava. Add a cobblestone platform and walls around it so the first step out is safe.
• Watch out for ancient debris on the way. Mining at Y=15 in the Nether is the best spot, as the netherite guide explains.

Frequently asked questions

How much obsidian do you need for a Nether portal?

You need 10 obsidian for the smallest portal. The corners of the frame are optional, so the 4 by 5 frame takes 10 blocks without them and 14 with them.

What is the biggest Nether portal you can make?

A frame of 23 by 23 blocks, with a 21 by 21 opening inside. Any rectangle from 4 by 5 up to that size works the same way.

How do you convert Overworld coordinates to the Nether?

Divide your X and Z coordinates by 8. Height stays the same, so only X and Z change when you convert.

Why are my Nether portals not linking?

The Overworld search reaches 128 blocks but the Nether search only 16, so nearby portals can grab the link. Build the Nether portal yourself at the exact Overworld coordinates divided by 8.

Can you use crying obsidian for a Nether portal?

No. Only regular obsidian works in the frame. Crying obsidian is used to make respawn anchors instead.

How long do you have to stand in a Nether portal?

Four seconds in survival, set by the default players_nether_portal_default_delay game rule of 80 ticks. In creative mode the trip is instant.