3D Model Converter
Move a model between a 3D printer slicer, a CAD program, a game engine and the web. Upload STL, OBJ, STEP, IGES, 3MF, GLB, FBX and other mesh or solid files, or a flat image, and get the format the next program expects, with the right units and orientation.
3D Model Converter
or drop STL, OBJ, MTL … files here ·
Max 95 MB per file· Up to 20 files· Deleted after 30 minutes
Files are processed on our servers and deleted after 30 minutes.
STL and OBJ store no units. If a part shows up 10× or 25.4× too small or too big in the slicer, the units were read wrong — set them here.
Blender, CAD programs and slicers use Z-up; glTF, Unity and most game engines use Y-up. Switch it if the model lies on its side after import.
Used when converting STEP or IGES solids to a mesh. Fine gives smooth curves but larger files; coarse is enough for quick previews.
Only used for PNG, JPG or SVG input. Relief raises dark areas; a lithophane is a thin panel that shows the photo when lit from behind; extrude turns a logo or SVG outline into a flat solid shape.
Width of the printed model; the height follows the image's aspect ratio.
Maximum raised height for a relief or lithophane, or the thickness of an extruded shape. Lithophanes usually use 2–3 mm.
Solid plate under the relief so the print holds together. 0 means no base.
How to use this tool
- 1
Upload models or images
Add up to 20 files, 95 MB each. Mesh and CAD files, a ZIP holding a model with its textures, or a PNG, JPG or SVG to turn into a printable shape are all accepted.
- 2
Choose the format and geometry
Convert to starts on STL. Under Advanced settings, set Model units, Up axis, Mesh detail for STEP or IGES solids, and, for image input, what the picture becomes and how big it prints.
- 3
Convert and download
Press Convert to STL, or the format you picked, and save each model or a ZIP. Uploads and converted models are deleted from the server after 30 minutes.
Every 3D format answers a different question: STL and 3MF tell a printer what to build, STEP and IGES tell a CAD program what the exact surfaces are, and glTF, FBX and USDZ tell a renderer what the model looks like. The converter translates between them and lets you correct units, axes and detail along the way.
- Models per batch
- 20
- Maximum size per file
- 95 MB
- Until uploads and results are deleted
- 30 min
- Output formats, from STL to DAE
- 10
STL, OBJ, STEP, 3MF, glTF and FBX compared
| Format | Origin | Geometry | Units | Color / textures | Typical use |
|---|---|---|---|---|---|
| STL | 3D Systems, 1987 | Triangle mesh | None stored | No | Slicers for 3D printing |
| OBJ | Wavefront Technologies, 1980s | Polygon mesh | None stored | Yes, via an MTL file | Exchange between Blender, Maya and others |
| STEP | ISO 10303, first parts 1994 | Exact solids and surfaces | Yes | No | Fusion 360, SolidWorks, FreeCAD |
| IGES | US National Bureau of Standards, 1980 | Surfaces and curves | Yes | No | Older CAD exchange (input only) |
| 3MF | 3MF Consortium, 2015 | Triangle mesh, multiple objects | Yes | Yes | Modern slicers and print services |
| glTF / GLB | Khronos Group, version 2.0 in 2017 | Mesh with PBR materials | Meters | Yes | Web viewers, Android AR, three.js |
| FBX | Autodesk, proprietary | Mesh, rigs and animation | Yes | Yes | Unity, Unreal, Maya, 3ds Max |
| USDZ | Apple and Pixar, 2018 | Mesh with materials | Yes | Yes | AR Quick Look on iPhone and iPad |
| PLY | Stanford University, 1990s | Mesh or point cloud | None stored | Per-vertex color | 3D scanning |
| DAE | COLLADA, Khronos Group | Mesh and scene, XML | Yes | Yes | Older game and SketchUp workflows |
The biggest divide is between meshes and solids. A mesh, such as STL, OBJ, 3MF or GLB, approximates every surface with flat triangles; a solid, such as STEP or IGES, stores the true cylinder, plane or spline. Going from solid to mesh is routine: Mesh detail decides how many triangles approximate each curve, with Coarse for quick previews, Normal for most prints and Fine for smooth visible surfaces. Going from mesh to solid, as in STL to STEP, wraps the triangles as faces but cannot recover the original design intent.
File encoding applies to STL, PLY and FBX. Binary is the default and is about five times smaller than ASCII, which writes every coordinate as text; a binary STL is an 80-byte header followed by 50 bytes per triangle. Choose ASCII only when a script or older tool needs to read the file as text.
Up axis fixes models that arrive lying on their side. CAD programs, Blender and slicers treat Z as up, while glTF, Unity and most game engines use Y; choose Y-up or Z-up to rotate, or Keep to leave the orientation alone. Merge into one mesh combines all parts into one object, and Keep textures & materials embeds colors and image maps wherever the target format allows.
Turn a PNG, JPG or SVG into a 3D model
Relief (height map)
Dark pixels are raised and light pixels stay low, like a coin or embossed sign. Good for photos and textures on plaques. Tick Invert heights to raise the light areas instead.
Lithophane
A thin panel whose thickness follows the photo, so it lights up when held against a lamp. Heights are set automatically so dark areas print thickest and block the most light; 2 to 3 mm is the usual range.
Extruded shape
The outline of a logo or SVG is pushed straight up into a flat solid, like a cookie cutter, keychain or sign letter. This is what PNG to STL uses.
Four numbers control the size. Model width runs from 5 to 1,000 mm (100 mm by default), and the height follows the image's aspect ratio. Height / depth is the maximum raised height for a relief or lithophane, or the thickness of an extruded shape, from 0.2 to 100 mm. Base thickness adds a solid plate underneath, 1 mm by default; 0 removes it. High-contrast images with clear edges give the cleanest results, and a 1,000-pixel-wide image is plenty for a 100 mm print.
Checks before you send a converted model to print
| Do | Don't |
|---|---|
| Measure one known dimension in the slicer right after import. | Expect an STL to remember whether it was drawn in inches or millimeters. |
| Use 3MF when the slicer reads it, so units and parts travel with the file. | Merge parts you want to print in different colors. |
| Pick Fine mesh detail for STEP parts with visible curved surfaces. | Use ASCII encoding for large meshes; it multiplies the file size. |
| Keep the STEP or native CAD file as the master for later edits. | Treat a mesh-to-STEP conversion as an editable parametric model. |
| Only convert models you made or are licensed to modify and print. | Rotate a model by hand in every program when Up axis fixes it once. |
3D model converter questions
Which 3D file format should I use for 3D printing?
STL works in every slicer, including Cura, PrusaSlicer, Bambu Studio and OrcaSlicer. 3MF is the better choice when the slicer supports it, because it stores units, colors and several parts in one file. Use 3MF to STL only when a program or printer service accepts nothing else.
Why is my model 25.4 times too small or too large in the slicer?
STL and OBJ files store bare numbers without a unit, and most slicers assume millimeters. A part drawn in inches therefore arrives 25.4 times too small. Set Model units to the unit the model was made in and convert again; a 10× error means centimeters were read as millimeters.
Can I edit an STL file in Fusion 360 or SolidWorks after converting to STEP?
You can import it, but you get a faceted body: every triangle of the mesh becomes a flat face. Fillets, holes and sketches are not recreated, so editing works for simple cuts and additions rather than parametric changes. STL to STEP is best for parts with mostly flat faces.
Do textures and colors survive the conversion?
Yes when both formats support them and Keep textures & materials is on: OBJ with its MTL file, glTF, GLB, FBX, 3MF, USDZ, DAE and PLY can carry them. STL and STEP cannot store textures, so colors are dropped when you convert to those.
How do I view a 3D model in augmented reality on an iPhone?
Convert it to USDZ. iPhone and iPad open USDZ files directly in AR Quick Look from Files, Messages or Safari, and you can place the model on a table at real scale. Android and the web use GLB for the same purpose.
What is a lithophane and how thick should it be?
A lithophane is a thin printed panel whose thickness varies with the photo, so it shows the image when light shines through it. Choose Lithophane under Image becomes; 2 to 3 mm for Height / depth with a thin base is typical, printed in white PLA.
Can I convert several parts into one file?
Upload one multi-part file, such as an FBX scene or a 3MF plate, and the parts stay separate objects in the output. Tick Merge into one mesh when a program expects a single object, and leave it off for multi-color printing where each part gets its own filament.
All 3D Model Converter tools
Pick the exact target you were asked for. Every page below is the same tool with different defaults.
- 3MF to STL ConverterConvert 3MF to STL for slicers, print services and tools that only read STL. Geometry is kept in millimeters; colors, plates and print settings drop out.
- FBX to OBJ ConverterConvert FBX files from Mixamo, Unity asset packs or Maya to OBJ with MTL materials and textures. Binary and ASCII FBX accepted, 20 files per batch.
- GLB to FBX ConverterConvert GLB to FBX with meshes, textures, skeletons and animation for Unity, Unreal Engine, Maya or Blender pipelines that expect Autodesk FBX.
- GLB to USDZ ConverterConvert GLB models to USDZ so iPhone and iPad users can place them in AR from Safari, Messages or Files. PBR materials and textures carried across.
- glTF to GLB ConverterPack a .gltf file with its .bin buffers and texture images into a single GLB. Upload the folder as a ZIP; the model, materials and scale stay unchanged.
- Image to STL ConverterTurn a JPG, PNG, WebP or BMP image into a printable STL: a raised relief, a backlit lithophane or a flat extruded shape. Set width, depth and base in mm.
- OBJ to GLB ConverterConvert OBJ with its MTL and textures into a single GLB for three.js, model-viewer, Shopify and Android AR. Scale set to meters, materials embedded.
- OBJ to STL ConverterConvert OBJ models from Blender, ZBrush or a scan into binary STL for 3D printing. Quads are triangulated, parts merged and the scale fixed to millimeters.
- PNG to OBJ ConverterConvert a PNG height map, logo or grayscale picture into an OBJ mesh for Blender, Unity or Godot. Choose relief or extruded shape and set the size in mm.
- PNG to STL ConverterConvert a PNG to STL as a lithophane panel: brightness becomes thickness, 0.8 to 3.2 mm, ready to print and light from behind. Relief and logo modes too.
- STEP to STL ConverterConvert STEP or STP files to STL for Cura, PrusaSlicer and Bambu Studio. Pick coarse, normal or fine mesh detail and get a binary STL in millimeters.
- STL to GLB ConverterConvert STL print files to GLB for websites, model-viewer and Android AR. Millimeters scaled to meters and Z-up turned to Y-up so the part stands upright.
- STL to OBJ ConverterConvert STL to OBJ for Unity, texturing tools and other 3D apps that expect OBJ. Shared vertices, readable text and the same triangles, in seconds.
- STL to STEP ConverterConvert STL meshes to STEP files that open in Fusion 360, SolidWorks and FreeCAD. Set the units the STL never stored, then download a faceted STEP solid.
- SVG to STL ConverterExtrude an SVG logo, lettering or silhouette into a solid STL for keychains, signs and badges. Set exact width and thickness in millimeters, no CAD needed.
- ZIP to STL ConverterUpload a ZIP from Thingiverse, Printables or a CAD export and get STL files back. OBJ, 3MF and STEP inside are converted; each part stays a separate STL.