Crafty Seed Map vs Seeder

Crafty Seed Map is a free web tool for Minecraft Java players who want to inspect seed terrain and locate biomes, slime chunks, and structures. It accepts numeric seeds and text seeds, hashing text as the game does, and can display the Overworld, Nether, and End. A nearest-search function works outward from an origin in a spiral and checks structure candidates against biome requirements. Named, colored markers are stored in the browser for each seed, while a shareable URL preserves the seed, viewport, visible layers, and biome highlight. World generation runs locally in the browser, and the seed is not sent to a server. The biome layer uses a WebAssembly port of cubiomes, and structure locations are revalidated against biomes. Supported versions are Java Edition 1.18.2, 1.19.4, 1.20.6, 1.21.1, and 1.21.3; Bedrock Edition is not supported. The map is described as mobile-first and includes pinch-to-zoom controls, with no ads. Buried treasure, mineshafts, geodes, desert wells, and end gateways appear only at sufficiently close zoom levels.

Seeder has no write-up on Specifiction yet; its figures are above.