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.

Direction

Precision

decimals

Applied to GeoJSON output (and before export).

Quantization (Q)

default 100 000

Higher Q preserves more detail but compresses less.

Simplify (0→1)

0 = none1 = max

Min area filter (m²)

m²

Remove tiny polygon rings below this area (0 = off).

Drop feature properties (maximum compression)

Prevent shape inversions on high simplify

Paste GeoJSON (or choose file)

Choose .geojson/.json

Result

No data yet.

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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).