Checker · measurements
STL dimensions and volume: measure before you print
How big is this STL, does it fit the bed, how much material will it use? Drop the file: the tool shows its bounding box in the unit of your choice, its surface area, its volume when the mesh is closed and its triangle count. Nothing leaves your device.
Nothing is uploaded: everything runs in your browser.
The unit, first cause of surprises
An STL contains no unit: just numbers. Most software exports in millimeters, but some in inches or meters. If the tool reports a 2 mm part, check the unit with the selector: in inches, those 2 units become 50.8 mm. The report converts to millimeters next to your unit so the mistake does not reach the slicer.
Volume and material estimate
The volume is computed exactly on the mesh, not on the bounding box, and only when it is closed and manifold. For filament, the volume in cm³ times the density (PLA ≈ 1.24 g/cm³) gives the mass of a solid part; with 20% infill, add the walls. For resin, the volume indicates the consumption of a solid part, supports excluded.
Triangles: too many or too few
A few thousand triangles are enough for a technical part; a detailed figurine needs hundreds of thousands. Beyond a million, the slicer slows down with no visible gain in the print. The count shown helps you decide whether to decimate in your 3D software.
How it works
Drop the STL
Up to 80 MB on a computer, 40 MB on a phone.
Pick the unit
Millimeters by default; centimeters, meters or inches if your export requires it.
Read the measurements
Dimensions, surface, volume if closed, triangles, and size warnings.
Frequently asked questions
- Why is the volume "not computable"?
- Because the mesh has open edges or non-manifold edges: a computed volume would be wrong. The watertight checker details those defects.
- Do the dimensions depend on orientation?
- They describe the bounding box aligned with the file's axes. A tilted part looks larger; orient it in the slicer.
- Can I get the weight?
- The tool gives the volume. Multiply it by your material's density for a solid part; the slicer computes the real mass with infill.
- Is my file uploaded?
- No. The measurements are computed in your browser.
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