TopoJSON Minifier

Use this tool to reduce your TopoJSON file size by removing unneeded properties from geometry objects and reducing the transform precision. It works entirely in your browser—no upload to a server.

Why minify TopoJSON?

TopoJSON encodes topology and uses integer quantized coordinates with a transform (scale, translate). Many files carry more decimals in the transform than necessary and include bulky properties that aren’t needed for rendering. Trimming the transform precision and pruning properties can substantially reduce file size, as can removing whitespace.

This tool helps you produce smaller, faster-loading TopoJSON by:

• Reducing transform precision (with an “Approx grid at the Equator” hint like the GeoJSON tool)
• Keeping only the properties you need (or quickly applying common presets)
• Optionally removing empty property objects and trimming whitespace
• Running entirely in your browser—no uploads

Support for large files

This free, client‑side tool is optimized for large datasets. On modern devices and browsers it can handle very big files—often 100MB or more—without freezing the page, thanks to background processing.