Simplify / TopoJSON

Compress and smooth your geometries using quantization and topology‑preserving simplification. Convert GeoJSON ⇄ TopoJSON with a live map preview.

No upload High compression Standards‑based
Tip: For best results, set a suitable Quantization first, then increase Simplify gradually while watching boundaries.
decimals
Applied to GeoJSON output (and before export).
default 100 000
Higher Q preserves more detail but compresses less.
0 = none1 = max
m²
Remove tiny polygon rings below this area (0 = off).
Result
No data yet.
—
Map Preview
Notes:
  • Quantization snaps coordinates to a grid for smaller arcs.
  • Simplify uses Visvalingam‑Whyatt effective area (topology‑safe).
  • Preview shows output geometry (TopoJSON is converted to GeoJSON for display).