3D model viewer: open OBJ, GLB, FBX, 3MF and STEP online

This 3D model viewer reads the file in your browser, so you don't need modeling software. Everything runs locally; the model is never uploaded to a server.

Format	Used for	Color, texture	Usual unit
STL	3D printing	none	mm
3MF	printing, slicer projects	possible	stored in the file, usually mm
OBJ (+ MTL)	model exchange, rendering	in separate files	varies
GLB / GLTF	web, AR, 3D scanning	embedded or separate	meters
PLY	3D scanning, point clouds	vertex colors	varies
FBX	animation, game engines	yes	often cm
DAE (Collada)	older model exchange	yes	stored in the file
STEP / STP, IGES / IGS, BREP	mechanical CAD	body colors	usually mm

CAD formats aren't triangle meshes but exact surface descriptions. On opening, a WebAssembly-based reader converts them to triangles on your device. The reader is about 7 MB and downloads only with the first such file. If you mostly work with these, see the STEP file viewer as well.

Some formats split a model across several files. OBJ holds only the geometry. Colors and materials live in a companion .mtl file, and images in separate JPG or PNG files. GLTF can reference a .bin data file and textures.

Select all the files at once, or drag them in together; the viewer matches them by name. If you add only the main file, the model shows up gray, with a warning naming the missing companion file.

GLB is the same as GLTF, packed into a single binary file, which makes it the easiest to share. Compressed GLB files (Draco, meshopt) are supported too; they're common in web models and exports from phone scanning apps.

Programs don't agree on which way is up. In 3D printing and CAD, Z points up (STL, 3MF, STEP). In web and game tools it's Y (GLB, OBJ, FBX). If the model lies on its side, toggle Z up. The measurements don't change, only the view.

Units differ the same way: GLB uses meters by spec, STL millimeters, FBX often centimeters. You can set the file unit to mm, cm, m or inches, and the display to mm or inches.

Example: a vase exported as GLB from a phone scanning app measures 0.12 × 0.12 × 0.25 units. In meters that's 120 × 120 × 250 mm (about 4.7 × 4.7 × 9.8 in), which makes sense. Read as millimeters, it would be the size of a grain of rice. Volume scales with the cube of the factor: switching from meters to millimeters multiplies the number by a billion (1,000³).

PLY is the go-to format for 3D scanners and photogrammetry software. It comes in two kinds:

• Mesh (with faces): measurable just like an STL, with vertex colors displayed.
• Point cloud (no faces): just points. They're drawn as dots and you get the bounding box size, but volume and surface area can't be computed because there's no closed surface.

Scanned meshes are rarely perfect. Often the bottom is open, because the object sat on a table, or small holes remain in shadowed areas. The mesh check highlights those open edges in red. On the Repair tab you can patch the holes before you send the model to print.

Most FBX, GLB and DAE models are made for screens, not printers. On screen, a surface only has to look right. A slicer needs a closed, solid body. So these models often:

• consist of open surfaces (clothing or hair as a single layer of triangles, for example);
• are built from separate pieces pushed into each other;
• have very thin parts that would snap when printed;
• have an odd size because they were made in another unit.

The viewer reveals all of this: the number of separate bodies, open and non-manifold edges, and wall thickness in the Section view. The Repair tab fixes simple errors. Surfaces that are open by design, like a single-layer cape, won't become a solid printable body through automatic repair; they need thickening in modeling software. Animations aren't played; the model is shown in its rest pose.

For every triangle-mesh model, you get the bounding box size, volume (cm³ or in³), surface area, and the number of triangles and separate bodies. Volume is exact only on a closed mesh; on an open one it's indicative.

More tools:

• Measure: click two points on the surface for the distance, with ΔX, ΔY and ΔZ.
• Section: cut the model along Z, X or Y with a slider and flip to the other half. The inside shows in red.
• Print: check the model against the beds of about two dozen printers and get a material estimate.
• Views: 3D, front, top and side, wireframe, grid, bounding box, model color.
• Screenshot: save the current view as PNG for a quote or a forum question.

If you need the model in another format, the 3D file converter turns it into STL, OBJ, GLB or 3MF.