Does MeshMedic upload or store my STL file?

No. MeshMedic processes the STL locally in your browser, so the model is not uploaded to a MeshMedic server.

Local processing · your file stays private

Browser-native STL diagnostics

Repair the mesh.
Keep the model.

Q: How do I repair an STL file online?

Drop an STL into MeshMedic, review the mesh diagnostics, select the repair operations you want, compare the original and repaired models, then download the repaired STL.

Q: What STL problems can MeshMedic detect?

MeshMedic detects open edges, non-manifold edges, degenerate faces, duplicate faces and disconnected shells.

Find topology problems, clean safe defects and export a slicer-ready STL. Nothing uploads. Nothing waits in a queue.

MODEL VIEWNo model loaded

↥

Drop your STL here

Binary or ASCII · up to 100 MB

MESH HEALTHAwaiting model

—/100

Your mesh report will appear here

We’ll inspect edges, faces, shells and surface orientation as soon as you add a model.

Featured printing partner

File fixed. Now make it real.

Take your repaired model from screen to finished part with Chichester 3D Printing.

CHICHESTER3D PRINTINGVisit the print studio ↗

01Private by design

Your STL is processed in this tab and never sent to a server.

02Changes you can see

Compare topology counts before exporting the repaired model.

03Slicer-ready output

Download a standard binary STL for your existing print workflow.

Free online STL fixer

Make broken 3D models printable again.

An STL can look correct on screen while still containing gaps, doubled triangles, inside-out surfaces or impossible edges. MeshMedic examines the triangle topology behind the model, shows you where common faults live and lets you choose which safe repairs to apply.

Fix non-manifold STL geometry

Find edges connected to too many faces—the kind of ambiguous geometry that can cause missing layers, strange toolpaths and failed slices.

Close straightforward mesh holes

Detect exposed boundaries and conservatively fill small, near-planar openings while leaving complex or uncertain geometry untouched.

Repair without uploading

Your STL stays on your device. Analysis, visualisation and repair run locally in the browser, with no server queue or model storage.

STL repair questions

Before you slice.

How do I repair an STL file online?+

Drop the STL into MeshMedic, inspect the highlighted issues, select your repair operations and compare the original with the repaired model before downloading.

Does MeshMedic upload or store my model?+

No. The file is parsed and repaired locally inside your web browser. It is not sent to a MeshMedic server.

What mesh errors can it detect?+

MeshMedic checks for open edges, non-manifold edges, degenerate faces, duplicate faces and separate shells. It can also weld matching vertices and recalculate surface normals.

Will automatic repair always preserve my design?+

No automatic tool can completely understand design intent. MeshMedic uses conservative operations and lets you review the result, but you should always inspect the final slice preview before printing.

Automatic repair can’t infer design intent. Always inspect the slice preview before printing.