Reduce 3D model file size online

Decimate and simplify STL, OBJ, GLB, and PLY meshes in your browser. Lower the triangle count while keeping the shape. Free, no upload.

Reduce the attached model to 25% of its triangles

Files are processed entirely in your browser. Nothing is uploaded to a server.

Any 3D edit is just a prompt away.
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How to reduce an STL file's size

Attach a model, pick how many triangles to keep, and press "Reduce it". The tool uses the meshoptimizer simplifier (the same algorithm game pipelines use) to collapse edges while preserving the overall shape and silhouette. A 100 MB scan usually shrinks to a few megabytes with no visible print difference.

Compare the before/after preview (toggle wireframe in the corner) and download the result as STL for printing or GLB for web and AR.

Frequently asked questions

Will decimation ruin my print quality?

Usually not. Most exported meshes carry far more triangles than a printer can resolve; a 0.4 mm nozzle can't reproduce detail smaller than the nozzle itself. Keeping 10-25% of triangles is typically indistinguishable on the printed part.

What's the best triangle count for printing?

Under one million triangles slices quickly in any slicer; under 200k is comfortable for sharing and web viewers. Use the size estimate shown next to the slider to hit a target file size.

Does this work with 3D scans?

Yes, scans are the main use case. If your scan also has holes or debris, run it through the repair tool afterwards to make it watertight.

More free 3D file tools

Repair a model Convert 3D files Measure a model Scale a model Split a model Mirror a model Print weight & cost

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