While no seed is 100% flat, are your best bet for a "mostly flat" start. These areas typically have a height variation of only about 7 blocks.
: This seed features a large, beautiful spot near the spawn. To find it, run up the hill at the spawn point and look to the right of the giant mountain. Steam Community Summary of "Fix" Options Effectiveness Ease of Use Tropics Biome High (flatter by default) Medium (requires travel) AdvancedWand Mod Maximum (perfectly flat) Hard (requires mod setup) Seed 1738427430 Moderate (large valleys) Easy (enter at start) Zero Seed (Legacy) Does not work in current versions console commands for managing land or steps on how to install the AdvancedWand colony survival flat world seed fix
User-facing mitigations (short-term)