Open .obj files free in your browser, with no account. Rotate and inspect the model, fix its scale, measure it properly, then export STL or 3MF to print it.
Drop the .obj on the plate (a model you downloaded from Printables, MakerWorld or Thingiverse, say) and it appears immediately — no upload wait, no account, nothing installed. Then do the thing most viewers cannot: measure it properly, and find out whether it will actually print.
Free to use · Runs in your browser · No upload wait
Opening the file is the easy part. What you usually need is a number: how big is it, will it fit, will it print.
Your browser reads and renders the .obj itself, so it appears the moment you drop it in — never queued behind anyone else’s upload, and the file does not travel anywhere to be shown to you.
Measure the geometry itself: edge lengths, a hole’s radius and diameter, an arc’s true length, a face’s area, an angle, and the smallest gap between two parts. Plus overall size, volume, and triangle count.
OBJ records no units at all, which is why the same file opens huge in one tool and tiny in another. Reinterpret it as millimetres, centimetres, inches, or metres in one click, with the resulting dimensions previewed each time, so you can see which reading is right.
Run the print check for thin walls, overhangs (areas that would need supports), non-watertight geometry (closed, with no holes, so a slicer reads it as solid), and whether it fits your printer’s build volume — and see what it would weigh and cost in filament.
Unlike a plain viewer, the same window is a full editor: scale to exact millimetres, cut and combine with real shapes (union, subtract, intersect), hollow it, and repair the mesh. Nothing to install and nothing to move it into.
Export STL or 3MF for a slicer such as Bambu Studio, PrusaSlicer, Cura or OrcaSlicer, OBJ or GLB for other 3D software, or SVG and DXF of a 2D projection for a laser cutter.
You do not need 3D software installed to look at a .obj file. It opens here, in a browser tab, with no account.
Drag the .obj onto this page or onto the editor’s build plate, or click to choose it. Your browser reads the file itself, so it appears straight away.
OBJ records no units, so check its dimensions first: if they look wrong, reinterpret it as millimetres, centimetres, inches or metres, with each reading previewed. Then orbit around it and measure edges, holes, and the gap between two parts.
Run the print check to see thin walls, overhangs, and whether it fits your printer, then export STL or 3MF for a slicer, or OBJ and GLB for other 3D software.
It opens on your device, it is saved to your workspace as you work, and it exports back out in the format your slicer wants.
Your browser reads and renders the model itself, so it appears as soon as you drop it in — you are never queued behind anyone else’s upload, and the file does not travel anywhere before you can see it.
Most online viewers forget your file the moment you close the tab. OwlCAD keeps the model in your own workspace and syncs it as you work, so it is still there when you come back to this browser. Create a free account and it follows you to any device, and your projects dashboard lets you delete anything you no longer want.
When you are done, export STL, 3MF, OBJ, GLB or STEP — the format your slicer or your colleague actually needs, not a project file that only opens here.
No download, no account needed — it opens in your browser in seconds.
Drop the .obj onto the build plate and it appears straight away — OwlCAD runs entirely in your browser. Rotate and zoom it, read its overall size, volume, and triangle count, and measure any part of it. No install, no account, and no upload to wait for.
Yes, and on the model’s own geometry rather than points you place by eye: edge lengths, hole radii and diameters, true arc lengths, face areas, angles, and the smallest gap between two parts. That is usually the whole reason for opening someone else’s OBJ.
Almost certainly not. OBJ records no units at all, so a model exported from Blender at scene scale, or authored in metres or inches, arrives at the wrong scale through no fault of the file. The bar shown on import reinterprets it as millimetres, centimetres, inches, or metres in one click and previews the resulting dimensions each time, so you can see which reading is right.
Its colours, yes — its textures, no. Each object in the file lands as its own named part: OwlCAD reads per-vertex colours where the file carries them, and each material’s colour from its .mtl library when you drop the .mtl (or a zip holding both) together with the OBJ. Texture maps are not applied.
You can change it. Unlike a plain viewer, the same window is a full CAD editor: scale to exact millimetres, cut and combine with parametric shapes, hollow it, repair non-watertight geometry (holes or inside-out faces a slicer can’t fill), and export again. If editing is what you came for, the OBJ editor page walks through it.
Yes. Viewing, measuring, editing, and exporting are free forever, with no watermark. Only AI generation is part of OwlCAD Pro.