What is the 3D File Converter?
A free online 3D file converter that runs entirely in your browser. Open STL, OBJ, GLTF, GLB, PLY, FBX, DAE, AMF and 3MF models and export them to STL, OBJ, GLTF, GLB, PLY, FBX or USDZ — with rigs and animations preserved. Your files are processed locally on your device and never sent to a server.
How to convert a 3D file online
From model to converted file in four steps — no account, no install, no upload.
Open your model
Drag in an STL, OBJ, GLTF, GLB, PLY, FBX, DAE, AMF or 3MF file, or click to browse.
Check it
It appears immediately under studio lighting, with vertex and face counts and real dimensions.
Adjust if needed
Rescale, fit to a target size, rotate, drop to the floor or swap to Z-up before exporting.
Pick a format
Choose STL, OBJ, GLTF, GLB, PLY, FBX or USDZ and the file downloads to your device.
Fixing the scale
rendered in this tool
The same model, the same camera, one slider moved. A GLB carries no real-world unit, so a logo authored in one program can arrive 113 mm across when you wanted 40. The converter reports the measured bounding box as you scale, so you set the size before you export rather than discovering it in the slicer.
Why use this 3D file converter
Most online converters upload your model to a server and hand it back flattened. This one runs in the browser and tries hard not to lose anything.
Nothing is uploaded
The file is read straight from disk and written back locally. Nothing is transmitted, so it keeps working with the network off.
Rigs and animations survive
Skinned meshes and animation clips carry through to GLTF and GLB — the part most converters quietly drop, leaving a broken skeleton behind.
Old textures recovered
Files using the retired specular-glossiness materials are detected and their colour textures rebuilt, instead of exporting a plain white model.
Compressed files supported
Draco-compressed, meshopt-compressed and KTX2-textured glTF all open normally, rather than arriving stripped of geometry or texture.
Fix the scale as you go
Uniform or per-axis scale, one-click unit presets, fit-to-size, rotation and a Z-up swap — so the output lands in the units you need.
Free, with no signup
No account, no watermark and no file-size ceiling beyond what your own device can hold in memory.
Which formats convert to which
Nine formats can be opened and seven written. What survives a conversion depends on what the destination format is able to store.
| Format | Open | Save | What it carries |
|---|---|---|---|
| STL | Yes | Yes | Geometry only — no colour and no unit of measurement. The 3D printing standard. |
| OBJ | Yes | Yes | Geometry and UVs. Materials live in a separate .mtl file. |
| GLTF | Yes | Yes | Everything — materials, textures, rigs and animation. JSON plus external buffers. |
| GLB | Yes | Yes | The same as GLTF but packed into one self-contained binary file. The safest choice. |
| PLY | Yes | Yes | Geometry and vertex colours. Common output from 3D scanners and photogrammetry. |
| FBX | Yes | Yes | Reading needs version 2013 or newer. Written as ASCII FBX geometry. |
| USDZ | — | Yes | Apple AR Quick Look. Open the file on an iPhone or iPad to place it in a room. |
| DAE | Yes | — | Collada. An older interchange format still produced by many CAD tools. |
| AMF | Yes | — | XML-based printing format, largely superseded by 3MF. |
| 3MF | Yes | — | Modern printing package. Unlike STL it records what a millimetre means. |
Common conversions
GLB or GLTF to STL, for printing
Slicers want a plain mesh. Converting to STL flattens the materials away and leaves the geometry — check the dimensions first, because glTF is measured in metres and most slicers expect millimetres.
STL or OBJ to GLB, for the web
GLB is one self-contained binary file and loads far faster in a browser or a product viewer than a mesh with separate material files alongside it.
Anything to USDZ, for Apple AR
USDZ is what iOS Quick Look reads. Convert, email the file to yourself, open it on an iPhone and the model appears in the room in front of you.
FBX to GLB, keeping the animation
FBX from a 3D package carries a rig and clips. Converting to GLB preserves both, so the model still moves once it is on the web.
Frequently asked questions
The questions that come up most often about converting 3D files in a browser.
Are my files uploaded to a server?
No. The converter reads the file directly in your browser, converts it there and writes the result back to your device. Nothing is transmitted, which is also why it still works once the page has loaded and you go offline.
Which formats can I convert between?
You can open STL, OBJ, GLTF, GLB, PLY, FBX, DAE, AMF and 3MF, and save as STL, OBJ, GLTF, GLB, PLY, FBX or USDZ. Draco-compressed, meshopt-compressed and KTX2-textured glTF files are decoded as well.
Will my rig and animations survive the conversion?
Yes, when you export to GLTF or GLB. Skinned meshes are re-bound to the exported skeleton and every animation clip is carried across. STL, OBJ and PLY have no concept of a rig, so converting to those formats keeps the geometry only.
Why does my converted model come out the wrong size?
Formats disagree about units. glTF and GLB are defined in metres, so a 1.8 m model reads as 1.8 in a millimetre-based slicer, while STL and OBJ store no unit at all. Use the scale presets in the Transform panel — ×1000 for metres to millimetres, ÷1000 the other way.
My model has no texture after converting. Why?
Usually the source stores its materials in the retired specular-glossiness format, which current 3D engines no longer read. The converter detects that and rebuilds the colour texture automatically. Note that STL and PLY cannot carry textures at all, so converting to those formats always discards them — export to GLB if you need the material.
Is there a file size limit?
The tool imposes none. The practical ceiling is your device's memory — very large meshes take longer to parse, convert and write, and text-based formats such as OBJ and ASCII STL are slower than their binary equivalents.
Related tools
3D Viewer
Open the same nine formats just to look at them — play animations, apply studio lighting, take cross-sections and save high-resolution renders.
Print Control
Orient, scale and repair a model for printing, estimate cost and time, and export G-code without installing a slicer.