STL Fixer
Drop a broken STL. It finds holes, flipped and non-manifold triangles, duplicate faces and overlapping parts — then repairs and merges them into one clean, watertight solid you can print. Everything happens in your browser: your file is never uploaded.
Making a mold of this object? FORMA LABS builds the 3D-printable mold frame around it — walls, clips, pour funnel and all. Try it free for 14 days →
Your model appears here.
Problem edges are drawn in colour.
Problem edges are drawn in colour.
What it fixes
Holes and cracks, T-junctions, flipped and inside-out triangles, duplicate and zero-area faces, paper-thin double walls, loose fragments — and overlapping parts, merged with a real boolean union.
Private by design
The repair engine runs on your computer, inside this page. Your STL is never sent anywhere, so it works for confidential parts too.
Free, no strings
No account, no watermark, no limits beyond what your browser can hold. It's the same repair engine FORMA LABS uses before building a mold.