How do I convert STL to GLB?

Run the local Zlim CLI (no API key needed): zlim optimize file.stl -o file.glb -p balanced. Or use the hosted REST API: create a job at POST /api/v1/jobs, PUT the file to the upload grant, mark the upload complete, then poll until the status is "succeeded" and download the signed result URL.

How much smaller will my STL model be after conversion?

Zlim typically reduces file size by 70–80% through mesh quantization, Draco compression, and texture optimization while preserving visual fidelity.

print · STL → GLB

Convert STL to GLB — optimized

STL is the 3D printing workhorse — pure triangle soup with no color or materials; Zlim cleans degenerate triangles and outputs a compact GLB.

Get an API key Read the docs

bash

zlim optimize model.stl -o model.glb -p balanced
# → model.glb  (70–80% smaller)

What is STL?

STL is the 3D printing workhorse — pure triangle soup with no color or materials; Zlim cleans degenerate triangles and outputs a compact GLB.

Zlim converts STL (.stl) to an optimized GLB file — typically 70–80% smaller than the source — without any manual mesh cleanup or format-juggling.

How to convert STL to GLB via the API

The hosted API is asynchronous: create a job, upload your STL file to the returned grant, mark the upload complete, then poll until it succeeds. See the full REST flow.

bash

# 1. Create a job → returns an upload grant (putUrl)
curl -X POST https://zlim.ai/api/v1/jobs \
  -H "Authorization: Bearer $ZLIM_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "filename": "model.stl", "options": { "preset": "balanced" } }'

# 2. Upload the bytes, then mark the upload complete
curl -X PUT "$PUT_URL" --data-binary @model.stl
curl -X POST https://zlim.ai/api/v1/jobs/$JOB_ID/complete-upload \
  -H "Authorization: Bearer $ZLIM_API_KEY"

# 3. Poll until succeeded, then download the signed result URL
curl https://zlim.ai/api/v1/jobs/$JOB_ID/result-url \
  -H "Authorization: Bearer $ZLIM_API_KEY"

How to convert STL to GLB via the CLI

The Zlim CLI runs the engine locally and in-process — no account or API key required (see the CLI docs):

bash

zlim optimize model.stl -o model.glb -p balanced
# → model.glb  (70–80% smaller)

STL vs. GLB — why convert?

STL was designed for manufacturing and scan workflows — it lacks material data and is uncompressed. GLB is the W3C/Khronos real-time standard: a single binary bundle, GPU-friendly, supported by every web viewer, AR framework, and game engine. Converting with Zlim yields a GLB that is 70–80% smaller than a naive export.

FAQ

Does Zlim support all variants of STL?

Zlim handles the most common STL variants (.stl). If your file uses a non-standard extension or proprietary sub-format, check the docs or contact support.

Will the converted GLB look the same?

Yes — Zlim preserves visual fidelity. Mesh topology, UV maps, and materials are retained. The reduction comes from compression and quantization, not geometry removal.

How long does the conversion take?

Most jobs complete in seconds. Large CAD assemblies or high-polygon meshes (50 MB+) may take 15–30 seconds.

Is there a file size limit?

The limit depends on your plan: 50 MB on Free, 250 MB on Pro, and 1 GB on Studio and Enterprise.

Convert STL to GLB now

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