How to Build a Nether Portal in Minecraft: Step-by-Step Guide

The Nether is the single biggest unlock in Minecraft survival. Blaze rods for brewing stands, nether wart for potions, quartz for building, ancient debris for netherite armour — almost every advanced system in the game starts with a purple portal. The problem is obsidian. Most beginners assume they need diamonds first, and that stops a lot of players before they ever build one.

That assumption is wrong. You can build a Nether portal without a diamond pickaxe, and this guide shows you exactly how. We cover two methods for collecting obsidian, exact frame construction step by step, how to craft and use flint and steel, and what you need to know before stepping through for the first time.

What You Need

The minimum materials to build and activate a Nether portal:

• 10 obsidian blocks — the minimum if you skip the four corner positions (corners can be any block, or left empty)
• 14 obsidian blocks — the full count if you want all-obsidian corners
• Flint and steel — 1 iron ingot + 1 flint, used to activate the portal

A diamond or netherite pickaxe is needed only if you plan to mine existing obsidian. If you use the lava mold method described below, you can skip it entirely.

The corner rule is the key shortcut most guides don’t mention: the four corner positions in a 4×5 frame are structurally optional. The game validates only the 10 frame positions along the edges. Filling corners with dirt, cobblestone, or leaving them empty reduces the obsidian requirement from 14 to 10 — a significant difference early in a run.^[1]

Method 1 — Mine Obsidian with a Diamond Pickaxe

Natural obsidian forms wherever a lava source block contacts water. The most reliable deposits are at Y-levels between -54 and -60, where underground lava lakes are common at the bottom of the world.^[3] Look for dark, slightly iridescent blocks surrounding still lava pools.

Only a diamond or netherite pickaxe yields an obsidian drop. Every other tool destroys the block without dropping it. Mining takes roughly 9.4 seconds per block even with a diamond pickaxe — plan for 90–140 seconds to collect a full stack of 10–14 blocks.^[3]

Before you mine: bring a water bucket to extinguish yourself if you fall into lava, at least one full food bar, and extra torches. Lava pools at deep Y-levels are the most common cause of death before players ever reach the Nether.

Method 2 — The Lava Mold Technique (No Diamond Pickaxe)

This is the method that removes the diamond requirement entirely. Instead of mining obsidian and placing it, you build the portal frame shape using cheap blocks, pour lava source blocks into the frame positions, then pour water over them. The lava converts to obsidian in place — already in the correct frame shape, no mining required.

Step by step:^[2]

1. Collect lava in iron buckets. Find a lava pool — common underground at Y -54 and below, or on the surface in badlands biomes. Fill 10–14 buckets, making sure you scoop from still surfaces (lava source blocks), not flowing lava. Flowing lava converts to cobblestone when water hits it, not obsidian.
2. Pick a flat location and clear a working area roughly 6×5 blocks.
3. Build the mold. Using dirt or any cheap block, create a temporary structure with gaps exactly where your obsidian frame positions need to go. Think of it as a stencil — only the frame positions matter, and the mold material gets broken away afterward.
4. Pour lava into each frame position — one bucket per block slot, until all 10 (or 14) frame positions contain a lava source block.
5. Pour water over the lava. Use a single water bucket from above, flowing across the lava. Each lava source block the water contacts converts to obsidian immediately.
6. Remove the mold by breaking the surrounding dirt blocks.
7. Activate with flint and steel. The frame is already in the correct position.

One thing to watch: scoop only from still lava (source blocks), not from moving lava streams. The conversion only works source block to obsidian, not flowing lava to obsidian.

Method 3 — Ruined Portals

Ruined portals spawn naturally in all Overworld biomes and in the Nether. They’re partially destroyed Nether portal frames surrounded by scattered obsidian blocks, crying obsidian, and a loot chest. The chest typically contains obsidian, gold items, flint and steel, and sometimes enchanted gear.^[2]

When you find one, check how many usable obsidian blocks are already in the frame. Often only 2–6 blocks are missing. Collect loose obsidian from the ground around the structure first, then check for crying obsidian in the frame — crying obsidian looks similar to regular obsidian but emits purple particles and cannot hold a portal. Replace any crying obsidian with regular obsidian before you try to activate.

A complete ruined portal with a nearby chest is one of the best early-game discoveries in Minecraft. The chest can provide everything you need to complete and light the portal on the spot.

How to Craft Flint and Steel

Flint and steel requires:^[4]

• 1 iron ingot — smelt iron ore in any furnace
• 1 flint — mine gravel; each gravel block has roughly a 10% chance to drop flint. A Fortune-enchanted shovel raises this to near-100%. Gravel is common in riverbeds, beaches, and underwater.

Place the iron ingot and flint anywhere in the crafting grid — no specific arrangement required. The resulting flint and steel has 64 durability, enough for dozens of uses.

Building the Portal Frame — Step by Step

The standard portal is 4 blocks wide and 5 blocks tall (outer dimensions). The inner opening is 2 blocks wide and 3 blocks tall — the minimum the game will activate. Here’s the exact construction sequence:^[5]

Step 1. Choose your location and stand where the base of the portal will be. Place 4 obsidian blocks flat on the ground in a row — this is the bottom edge of the frame. (If saving obsidian, place only 2 in the middle positions and use any block for the two corners.)

Step 2. On the leftmost block of the base, stack 3 more obsidian blocks directly upward. You now have a left column of 4 blocks total (base block + 3 above).

Step 3. Repeat on the right end of the base — 3 obsidian stacked on the rightmost block. Two columns of 4, with 2 empty blocks between them.

Step 4. Lay 4 obsidian across the top, connecting the peaks of both columns. (Again, 2 centre blocks + corners of any material if saving obsidian.)

Step 5. Check the interior: you should see a clear 2×3 opening. If you look through the gap, no blocks should be blocking it.

If the portal doesn’t activate after lighting, a gap in the frame is almost always the cause. Walk around all four sides and check every position. One missing block prevents activation.

Activating the Portal

Select flint and steel and use it on one of the obsidian blocks on the inside face of the frame — aim at the inner edge of any frame block. A single right-click in Java Edition, or the interact button on console and mobile, is enough.

When the portal activates:^[1]

• The interior fills with swirling purple portal blocks
• A low, resonant ambient hum begins
• The purple vortex animates continuously

If you accidentally use flint and steel on the outer face of an obsidian block, it places fire on the block rather than lighting the portal interior. Make sure your cursor is aimed at the inner-facing surface.

Your First Steps in the Nether

Stand inside the purple blocks and hold still — after 4 seconds, you’ll be transported.^[1] A matching portal generates in the Nether at your arrival coordinates automatically. When you first arrive:

Turn around immediately and confirm your return portal is accessible. It should be directly behind you. If it spawned inside a netherrack wall or over a lava drop, note the coordinates right away (F3 in Java Edition) before wandering anywhere.

Assess for ghasts before moving. Ghasts are large, white, floating mobs that fire explosive projectiles. A ghast fireball hitting the interior of your portal deactivates it. They spawn above lava seas and in soul sand valleys — scan the sky before leaving the portal area.

Recommended gear for first entry: iron or diamond armour, a sword, a bow with arrows (deflecting ghast fireballs by hitting them back is possible and satisfying), a stack of cobblestone for emergency shelter and portal protection, food, and flint and steel to relight the portal if it gets deactivated.

Finding a Nether Fortress: Fortresses are the primary target on your first trip. These large dark brick structures contain blazes (which drop blaze rods, required for brewing stands and the End portal) and nether wart (required for all potions). They typically spawn within a few hundred blocks of your starting portal, most often to the north or south.^[2]

The Coordinate System

The Nether compresses horizontal distance by a factor of 8 — one block of travel in the Nether equals 8 blocks in the Overworld. This makes the Nether useful for fast travel: walking 100 blocks underground covers the same Overworld distance as walking 800 blocks on the surface.^[1]

Portal linking works on this ratio: your Overworld portal at X=800, Z=200 links to a Nether portal at approximately X=100, Z=25. If you build a second Overworld portal more than 128 blocks away from the first, it will attempt to create a separate Nether-side portal instead of linking to the existing one.

For a first portal this needs no action — the game handles linking automatically. The ratio becomes useful when building a portal network for fast travel between distant Overworld locations.

Portal Safety Tips

Secure the Overworld portal. Zombie piglins and other Nether mobs can walk through open portals and accumulate in the Overworld without despawning. Enclosing your portal in a dedicated room prevents mob escape into your base.^[2]

Never use crying obsidian in the frame. Crying obsidian looks similar to regular obsidian and appears in ruined portals, but cannot activate a portal. Check every block if you’re using salvaged materials.

Always carry flint and steel in the Nether. A deactivated portal doesn’t require rebuilding — just reignite the interior with flint and steel. Keeping it in your hotbar turns a potential crisis into a 2-second fix.

Enclose the Nether-side portal in cobblestone. Netherrack has very low blast resistance and disintegrates under a ghast fireball. A 1-block-thick cobblestone shell around the portal — just enough to block direct hits — dramatically reduces deactivation risk on return trips.

Quick Reference

Conclusion

Building a Nether portal is the pivot point where Minecraft survival stops being about day-to-day resource gathering and opens up into a full progression system. The lava mold technique removes the biggest barrier — you don’t need diamonds to get through the portal, and you never did.

Ten obsidian blocks, a flint and steel, and five minutes of careful construction is all it takes. Light the frame, bring cobblestone and food, and note your return portal coordinates before you start exploring. Once you’re through, find the Nether Fortress. Everything else follows from there.

References

1. Minecraft Wiki. “Nether Portal.” Minecraft Wiki, accessed March 2026.
2. Minecraft Wiki. “Tutorial:Nether portals.” Minecraft Wiki, accessed March 2026.
3. Minecraft Wiki. “Obsidian.” Minecraft Wiki, accessed March 2026.
4. Minecraft Wiki. “Flint and Steel.” Minecraft Wiki, accessed March 2026.
5. DigMinecraft. “How to Make a Nether Portal in Minecraft.” DigMinecraft, accessed March 2026.

Michael R.

I've been playing video games for over 20 years, spanning everything from early PC titles to modern open-world games. I started Switchblade Gaming to publish the kind of accurate, well-researched guides I always wanted to find — built on primary sources, tested in-game, and kept up to date after patches. I currently focus on Minecraft and Pokémon GO.