Check a seed
Paste a seed to see what is around spawn: biome, nearest structures with coordinates, biomes and the seed score.
Know a seed before you play it
Starting a world on a seed someone shared? Check it first: you see the spawn biome, how far the first village is, where the stronghold sits and whether the rare biomes are in reach. Then open it on the seed map to look around, or go back to the seed finder to look for a better one.
Questions
What does the seed check show?
The spawn point and its biome, the nearest of every structure the edition generates (with coordinates and distance from spawn), the nearest of each main biome, whether spawn is on a survival island, and the seed score with the reasons for it.
Where do I find my world's seed?
Java: type /seed in chat. Bedrock: open the world settings; the seed is under Game. Paste it here with the same edition and version.
Is anything sent to a server?
No. The world is generated in your browser, the same way the seed map does it.