Drop in a broken STL, OBJ or 3MF. It finds the holes, bad edges, inside-out faces and loose bits, then repairs the file for the machine that will make it.
Your file never leaves your computer. Everything runs inside this page. There is no upload and no signup.
Drop an STL, OBJ or 3MF here, or click to choose
Up to about two million triangles on an ordinary computer.
Your browser cannot show the 3D preview, but the repair and the download work as normal.
Drag to turn, scroll to zoom, double-click to reset. holes bad edges crossing faces inside-out or open (seen from behind)
| Check | Original | Repaired |
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Making it on a router? Check the repaired file in Will it cut? for bit sizes and cut time. Burning it on a laser? Laser Studio turns depth maps and photos into finished laser files.
No. The repair runs inside this page, in your browser. There is no server to send it to. Load the page, switch off your wifi and it still works.
Because each machine needs something different. A CNC router can only reach what it sees from above, so the file is rebuilt as a clean 2.5D relief with a flat back. A printer needs a closed 3D solid with the faces pointing outwards and a flat side on the bed. A laser burns from a greyscale image, not from an STL, so it gets a depth map.
Holes, non-manifold edges, repeated and broken triangles, inside-out faces, hairline cracks, loose fragments, open surfaces with no thickness, wrong units, the wrong side facing down, and triangle counts too large for the job. For CNC and laser the rebuild also removes undercuts and faces that pass through each other.
For printing, faces that pass through each other are left for the slicer, which merges overlapping volumes when it slices, and walls that are too thin are flagged rather than thickened, because thickening changes the design. Both are counted in the results so you know they are there.
They are only shown when the repaired file passes the same checks that found the problems: no holes, no bad edges, no broken or repeated triangles, every face pointing outwards. If something is still wrong, the badge is not shown and the row stays red.
STL files carry no units, which is why a model often arrives 25.4 times too small. If the size looks like inches, the tool converts it and says so; change it under Options. 3MF files do record their units, and those are used as they are.
Files of about two million triangles work on an ordinary computer and take under a minute. The check for faces crossing each other is skipped above 700,000 triangles, and the results say when it was skipped.
Every design here is checked watertight with a flat back before it is released. Drop any of them in above and see.
Built by DigitalChiselCo. If it gets your file wrong, tell us and we will look at it. More free tools on the tools page.
