Minecraft 1.21 Seed Map

A Minecraft seed is a number or text string used to initialise the world generator. The same seed always produces the same terrain, biomes and structures, so players can share seeds to explore identical worlds.

In single-player, run the command /seed in chat to reveal the seed. On servers you need operator permissions, or access to the savegame files, to read the seed.

No. Java Edition and Bedrock Edition use different world-generation algorithms, so the same seed produces completely different worlds in each edition. Always pick the matching edition before generating the map.

Structure markers are verified up to 99% accurate — villages, strongholds and ocean monuments are the most reliable, and every marker shows its own exact percentage the moment you open it. A few types like dungeons are lower, and some terrain-dependent features are shown as estimates rather than a number. Bedrock figures can be a little lower than Java, because Bedrock places some structures differently even on the same seed.

The map colours are biome colours, not the water level. Terrain inside a land biome often drops below sea level — river valleys, lake basins, flooded lowlands — and is still drawn in its land colour, so a bay or lake in your world can look green here; conversely, ocean and river biomes can contain small patches of land. Terrain estimation adds relief shading that makes those low basins easier to spot, but it does not repaint them as water.

Check that you entered a valid seed with no trailing spaces, and that you picked the edition and version that was used to generate the chunks you are looking at. If the problem persists, try a different browser – the viewer uses modern web features such as WebAssembly and Web Workers.

Yes. Right-click (or tap-and-hold on mobile) on the map to drop a temporary marker, then save it with a name and colour. Markers are stored locally in your browser for the current seed, edition and dimension — and if you sign in with a free account, they also sync across your devices.

That depends on how you play. For single-player exploration or finding specific biomes for a build it is generally fine. On multiplayer servers, check the server rules first – some servers do not allow seed-based tools.

Yes. Sulfur Caves — the cave biome added in Minecraft 26.2 (Java) and Bedrock 26.30 — can be located on the map. Choose version 26.2 or 26.30, set the biome height to Underground, then highlight Sulfur Caves in the biome list.

Several biomes are named differently in Bedrock Edition — for example Badlands is called Mesa, Windswept Hills is Extreme Hills, Dark Forest is Roofed Forest, Snowy Plains is Ice Plains and Mushroom Fields is Mushroom Island. Select the Bedrock tab on the map and the biome list and labels switch to Bedrock names automatically; the biome search box also accepts either edition's name. The full Java-to-Bedrock biome name list is shown above.

By default everything is saved locally in your browser only. Create a free account and sign in, and your saved seeds, custom markers and completion check-offs sync automatically to every device you use — the seed map itself works exactly the same with or without an account.

Almost always it is a version or edition mismatch. Java and Bedrock generate completely different worlds from the same seed, and even within one edition the structure layout changes across major updates. Check that the edition and the exact version selected above the map match the world you are playing, then regenerate. Some markers are chunk-centre approximations, so the real structure can sit a few blocks from the marker; and on rare occasions a marker fails to render, which reloading the page fixes.

Open the seed map's Advanced settings (the gear icon) and switch on the world border, then set the center point and radius. The map draws the playable area as a square — matching Java Edition's /worldborder — or a circle, with a live block-size readout that follows pan and zoom. A copy button gives you the exact /worldborder center and /worldborder set commands to recreate the same border in your world. Bedrock Edition has no vanilla /worldborder command, so there the border is shown for planning only.

Yes. You can install the seed map to your home screen as a Progressive Web App (PWA), straight from your browser and with no app store needed. On Android or desktop Chrome, use the Install app button (or your browser's install icon) to add it; on iPhone or iPad, open Safari's Share menu and choose Add to Home Screen. It then opens full-screen like a native app — but it is a web app, so there is no separate store download.

No — the world seed has nothing to do with it. Enchanting table offers come from your character's own enchantment seed, which re-rolls every time you enchant something. Two players on the same world see different offers, and the same player sees new ones after every enchant. What the seed cannot change is the set of enchantments the table is allowed to offer and how likely each one is — that depends only on the item and your bookshelf count.

The Ore Finder reproduces Minecraft's own ore-placement maths from your world seed, entirely in your browser. It runs the same ore-distribution and cave-carving steps the game uses, then marks the chunks where diamonds, netherite and other ores are most likely to be exposed. Nothing is uploaded – your seed never leaves your device.

Where an ore ends up depends on the exact terrain and caves Minecraft carves around it, and no in-browser tool can rebuild every block the game places. We reproduce that terrain very closely, so a hotspot marked with a high percentage really contains the ore in your world around 85–94% of the time on Java, and 85–93% on Bedrock — the per-ore figure for the edition you picked is on the badge and in the table above. A few spots may have been carved away by a cave or shifted slightly, so treat the markers as very strong leads rather than a guarantee.

In the Overworld it finds diamond, iron, copper, gold, redstone, lapis lazuli and coal, and in the Nether it finds ancient debris (netherite). You search one ore at a time and can optionally limit the search to a specific Y level.

Diamonds get more common the deeper you dig, peaking around Y -59 in current versions (they generate between Y -64 and Y 16). The finder defaults to each ore's full spawn range, and you can tick 'limit to a specific Y level' to focus on the richest band – for diamonds, around Y -59 to -54.

It works on both Java and Bedrock Edition. On Java it covers modern versions, including 1.21 and the 26.x releases, which share the same ore-generation rules. Bedrock Edition is now supported as well – on 1.18 and newer it finds the Overworld ores (diamond, iron, copper, gold, redstone and lapis lazuli). The two editions use different world generators, so make sure you pick the edition your world was created in.

That is up to how you like to play. In single-player it is just a faster version of strip-mining for a diamond start. On multiplayer servers, check the rules first – some servers don't allow seed-based tools.