100% Free · No Signup · Files Never Stored

Fix Your STL Files Instantly

Repair non-manifold meshes and prepare print-ready 3D files in seconds. Just drag & drop your file.

Drop your 3D file here

Or click to browse — we'll repair it in seconds

STL OBJ FBX GLB GLTF PLY
Your files are never saved or stored on our servers
Up to 100MB Processed securely over HTTPS Deleted immediately after repair
API This tool runs on the Remeshy API — use it in your own workflow →
Repairing your mesh
00:00
1 ✓
Uploading securely
Encrypted in transit — file will be deleted after repair
2 ✓
Analyzing topology
Detecting non-manifold edges and holes…
3 ✓
Repairing mesh
Fixing edges, filling holes, rebuilding normals…
4 ✓
Optimizing for 3D printing
Preparing print-ready STL and OBJ files…
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Repair complete

Doing this often?

Process thousands of STLs via the API

Same engine you just used — wire it into your pipeline with webhooks, batch jobs, and signed download URLs.

View API docs
01 / REPAIR

Non-Manifold Repair

Automatically fixes non-manifold edges and vertices that cause 3D printing failures.

02 / OUTPUT

Print-Ready Output

Get STL and OBJ files optimized for any 3D printer. Works with FDM, SLA, and SLS.

03 / FREE

Fast & Free

No signup, no limits, no waiting. Fix your files instantly in your browser.

Tired of Fixing Broken STLs?

Every model Remeshy generates is print-ready by default — no non-manifold edges, no holes, no failed prints. Describe what you want, get a printable STL in seconds.

Generate a Print-Ready Model Browse Free Models
DEEP DIVE

Why do STL files break? Understanding non-manifold geometry

Non-manifold geometry is one of the most common issues that causes 3D printing failures. A mesh is considered "non-manifold" when it contains edges shared by more than two faces, vertices connecting separate mesh sections, or faces with inconsistent normals. These issues make it impossible for a slicer to determine what is "inside" versus "outside" the model.

Common causes include: boolean operations in CAD software that leave internal faces, importing models from AI 3D generators that create overlapping geometry, merging multiple meshes without proper cleanup, and scaling operations that create zero-area faces.

Remeshy's STL repair tool automatically detects and fixes these issues by removing degenerate faces, filling holes, correcting normals, and ensuring watertight geometry. The result is a print-ready mesh that works with any slicer — whether you're using Cura, PrusaSlicer, or Bambu Studio.

For more complex topology issues like high-poly cleanup and quad remeshing, try our mesh optimizer. To learn about professional retopology workflows, read our complete retopology guide. Or browse our free 3D printables library for ready-to-print models.

WATCH

See STL repair in action

A quick walkthrough of repairing a broken STL with Remeshy — turning a non-manifold mesh into a watertight, print-ready file. Want to do it yourself? Drop your file at the top of this page.

For developers

Using this at scale? There's an API for that.

Drop a URL, get back a print-ready STL. Webhooks notify you on completion — no polling required. Batch thousands of files, integrate into game engines, or add print-prep to your own product.

curl -X POST https://api.remeshy.com/api/jobs/print-ready \ -H "X-Api-Key: rms_live_your_key" \ -H "Content-Type: application/json" \ -d '{ "file_url": "https://example.com/broken.stl", "webhook_url": "https://your-app.com/webhook", "settings": { "output_formats": ["stl", "obj"] } }'
Read the docs Get an API key
FAQ

Frequently asked questions

No. Your files are processed over HTTPS, repaired, and deleted immediately after you download the result. We never save, store, train on, or share your 3D files. Every upload is processed in an isolated workspace and removed as soon as processing finishes.
A non-manifold mesh has geometry that cannot exist in the real world — edges shared by more than two faces, internal faces, or vertices connecting separate mesh parts without proper topology. These issues prevent 3D printers from understanding the model's solid volume, causing print failures.
STL files commonly develop issues from boolean operations in CAD software, AI generation overlapping geometry, merging multiple meshes, or file conversions. Without repair, slicers can't calculate toolpaths and you'll experience failed prints or missing sections.
Remeshy accepts STL, OBJ, FBX, GLB, GLTF, and PLY files. After repair you can download in STL or OBJ format — compatible with all major slicers including Cura, PrusaSlicer, and Bambu Studio.
Most repairs complete in under 60 seconds. Complex meshes with millions of polygons may take 2–3 minutes. Processing happens on our servers so your device speed doesn't matter.
Remeshy preserves geometry as much as possible, typically retaining 80–95% of original shape while fixing all manifold issues. The repair report shows exactly what was changed.
Yes — this tool is a live demo of the Remeshy STL Fix API. The same /api/jobs/print-ready endpoint handles individual repairs here and batch workloads for production. Submit files by URL, get back signed download links for the repaired STL and OBJ. View the STL Fix API docs.
Yes. Pass a webhook_url when you submit a job and Remeshy will POST the completed job (with download URLs and repair stats) to your endpoint as soon as processing finishes — no polling required. HMAC-SHA256 signatures via webhook_secret are supported for production verification.
Sign up at the API dashboard to get a key. Pricing is credit-based with volume tiers — STL repair jobs consume a small fixed number of credits each, with discounts for high-volume customers. Free trial credits are included so you can integrate before committing. See pricing.
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