# 3D file formats: which go on your webshop? > A STEP from your manufacturer, an FBX from your designer: which 3D file goes on your webshop? What each format is, and how to convert it to GLB. Canonical: https://www.virtualdisplay.io/en/blog/3d-file-formats Language: en Also available in Dutch: https://www.virtualdisplay.io/kennisbank/3d-bestandsformaten Last updated: 2026-10-18 --- A STEP from your manufacturer, an FBX from your designer: which 3D file goes on your webshop? What each format is, and how to convert it to GLB. **Date:** October 15, 2026 Your manufacturer sends a STEP file, your designer delivers an FBX and a colleague found an STL online. All 3D, and none of them works on your product page. That needs a GLB: the format made for the web. This article explains why, what each format contains and how to convert it to GLB. ## Why can't a browser show every 3D format? Every 3D format was made for its own use. A manufacturer draws products in CAD software, to a tenth of a millimetre, so a machine can make them. A game studio makes characters that move. A 3D printer builds an object out of plastic. Each of these has its own format, and none was made to load fast on a phone. Think of photos. Your photographer works in RAW: large files full of data for editing. On your webshop you use a JPEG. It is smaller, ready to show and every browser opens it. In 3D, GLB is that JPEG. The shape and the materials, down to the grain of the wood, sit together in 1 small file. Every browser opens it, on a laptop and on a phone. Your visitor installs nothing and sees your product straight away. Next to GLB there is glTF. It is the same standard, split over separate files. Handy while building a model, less so on a webshop. Our article on [glTF and GLB](https://www.virtualdisplay.io/en/blog/gltf-explained.md) explains the difference. ## What do you do with your manufacturer's STEP files? STEP (also .stp) is the format CAD programs use to exchange drawings. Manufacturers design their products for production in CAD programs such as SolidWorks and Fusion. Furniture makers often draw their collection in CAD too. Chances are STEP files of your sofas, cabinets and tables already exist. Ask your manufacturer. A STEP file describes shapes with maths: a curve is a perfect curve, a drill hole exactly 8 millimetres. That keeps the dimensions right. It matters when your visitor places the sofa in their living room with AR. But a browser doesn't calculate with mathematical shapes. It builds a model from thousands of small triangles, like a mosaic. And a STEP file has no materials: no wood, no leather, no colour. All you see is a grey shape. So STEP to GLB takes 3 steps. First the shape becomes triangles. Then the count comes down, because CAD software often produces hundreds of thousands, even for a screw nobody sees. Then the materials go on, so wood looks like wood and leather like leather. You can do the first step yourself with the free program [FreeCAD](https://www.freecad.org/downloads.php). Open the STEP file, select the model and choose File, Export, with Wavefront OBJ as the format. For reducing the triangles and adding the materials you need someone with 3D experience. It is still less work than a model from scratch, because the shape and the dimensions are already there. Left: just the shape, as you get it from a STEP or STL file. Right: the same model with materials, ready for your product page. ## And if your designer delivers an FBX or OBJ? FBX comes from animation and games. Things move there, so an FBX can hold more than your product: movements, sometimes also the lighting and the viewpoint from the maker's program. On your product page the viewer handles the light and your visitor picks the angle. You leave those extras out when you convert. OBJ is older and simpler. An OBJ is several files: the shape in an .obj file, the materials in an .mtl file and the textures as separate images. Textures are photos of the surface, like the grain of the wood or the weave of the upholstery. If 1 file is missing, your model opens grey. So with an OBJ, always ask for the whole folder. You convert both in [Blender](https://www.blender.org/download/). It's free, and the 5 steps below show how. After converting, take a good look at your product. Does it look different from the photo? Has the wood turned glossy, or does the leather look like plastic? Then the materials didn't come through. If only a texture is missing, you can fix that yourself: see step 4 below. If the materials themselves are wrong, someone has to set them up again. That takes experience with 3D software. Send the file back to your designer, or [send it to us](https://www.virtualdisplay.io/en/contact.md). ## Is an STL enough? STL is the format of 3D printers. A 3D printer builds an object layer by layer out of melted plastic. It only needs to know where the plastic goes. The colour comes from the plastic in the printer, not from the file. That's why an STL holds only the shape. Think of an STL as a plaster cast of your product. The shape is right, but everything is one colour. Convert an STL to GLB and your product shows up grey on your product page. Your visitor can't see which fabric or colour they are buying. As a starting point an STL is useful. A 3D artist, someone who makes 3D models, takes the shape and adds the materials. If the dimensions are right, that saves work. ## Do you need a USDZ too? USDZ is the format Apple uses for AR on iPhone and iPad. It seems logical to have a USDZ made next to your GLB. You don't need to. A good viewer converts your GLB to USDZ the moment an iPhone visitor taps the AR button. That way you keep 1 file per product and AR works on Android and iPhone. [What is a GLB file?](https://www.virtualdisplay.io/en/blog/what-is-a-glb-file.md) explains how that works and what to ask your 3D supplier for. ## All formats at a glance Got a file and want to know what to do with it? Look it up here. | Format | Usually comes from | Works on your webshop as is? | What to do with it | | --- | --- | --- | --- | | GLB (.glb) | 3D studios, Blender, Sketchfab | Yes | Upload it | | glTF (.gltf) | 3D artists while they work | Yes, but better as GLB | Have it bundled into 1 GLB file | | USDZ (.usdz) | Apple apps and AR studios | Only for AR on iPhone | Nothing: your viewer makes it from your GLB | | FBX (.fbx) | Designers and game studios | No | Convert to GLB | | OBJ (.obj) | Older 3D software and model libraries | No | Convert to GLB and check the materials | | STL (.stl) | 3D printing | No | Convert and add materials | | STEP (.step, .stp) | Manufacturers and CAD software | No | Have it turned into a light model with materials | ## Convert it yourself in Blender: 5 steps Have an FBX, OBJ or STL and want to try it yourself? Download Blender for free from [blender.org](https://www.blender.org/download/). ### Import the file Open Blender. Every new file starts with a cube: click it and press Delete. Then choose File, Import and the format of your file: FBX, Wavefront (.obj) or STL. Have a STEP? Convert it to OBJ in FreeCAD first. ### Count the triangles Top right in the 3D view is an icon with 2 overlapping circles: Viewport Overlays. Click the arrow next to it and tick Statistics. Top left you now see under Triangles how many your model has. Under 100,000 is good. A phone redraws every triangle as soon as your visitor turns the model. With too many, turning stutters and the file takes longer to load. - 1: the arrow next to Viewport Overlays, where you tick Statistics. 2: Triangles shows the number of triangles. This bathroom vanity has 25,071. ### Reduce the triangles More than 100,000? If your model is made of several parts, join them first: move your mouse over the 3D view, press A to select everything, then Ctrl+J. Open the wrench tab on the right (Modifiers). Choose Add Modifier, Generate, Decimate. Set Ratio to 0.5 and you keep half the triangles. Then look closely at your product from every side. If you see corners in the curves, raise the Ratio a little. - Left: 25,000 triangles and the tap is round. Right: 1,500 and you see corners in the bend. Don't go that far down. - 1: the wrench tab. 2: Add Modifier, then Generate and Decimate. 3: Ratio at 0.5. 4: the vanity now has 12,535 triangles, half as many. ### Check materials and dimensions Click the third sphere top right (Material Preview) to see your model with its materials. Is part of it pink? Then a texture is missing. Choose File, External Data, Find Missing Files and point to the folder with the images. Don't have that folder? Ask whoever sent you the file. Then press N: under Item, Dimensions shows the size in metres. A sofa 2.4 metres wide should read 2.4 m there. - 1: Material Preview, the third sphere. 2: pink means a texture is missing, here the oak of the cabinet. 3: after N you see the size under Dimensions. This vanity is 1.2 m wide. ### Export as GLB Choose File, Export, glTF 2.0. Set Format to glTF Binary (.glb) and tick Compression. Then drop the file into [gltf.report](https://gltf.report) to see its size and triangle count. Under 5 MB? Upload it in [Portal](https://www.virtualdisplay.io/en/solutions/portal.md). ## Rather not do it yourself? Converting a STEP file or an FBX without textures takes experience with 3D software. We're happy to do it for you. You get a model with the materials of your collection that loads fast on a phone and goes straight on your product page. [Send us your files](https://www.virtualdisplay.io/en/contact.md) and we'll tell you what it needs. ## Already have a GLB? Upload it to Portal and you have an embed code for your product page within minutes. Your first model is free. - [View Portal](https://www.virtualdisplay.io/en/solutions/portal.md) - [Get in touch](https://www.virtualdisplay.io/en/contact.md) --- Source: https://www.virtualdisplay.io/en/blog/3d-file-formats Published by Virtualdisplay, Rotterdam, Netherlands. Full site index for agents: https://www.virtualdisplay.io/en/llms.txt