Get the Dimensions of an STL File
Drop an STL (or any 3D file) to read its exact width, depth and height, bounding box, volume, surface area and triangle count. Runs in your browser, nothing is uploaded.
How it works
- 1Drop the STL
Any mesh or CAD format works, not only STL.
- 2Read the size
Width, depth and height appear immediately, with volume, surface area and triangle count below.
- 3Switch units
Toggle inches if the model was designed in imperial units.
Details
STL files do not store a unit. Slicers assume millimeters, so a model designed in inches arrives 25.4 times too small. Reading the bounding box before slicing tells you immediately whether the numbers make sense for the object you expect.
Volume is computed from the signed volume of every triangle, which is exact for closed meshes. If the mesh has open edges the volume is an approximation and the panel flags it. Multiply the volume by your filament density (PLA ≈ 1.24 g/cm³) to estimate weight.
Accepted formats: STL, OBJ, 3MF, PLY, GLB, glTF, STEP, STP, FBX, DAE, AMF, VRML, 3DS, IGES, IGS
Frequently asked questions
More STL tools
- Reduce STL File Size (Simplify Mesh)
Cut the triangle count of an STL file by a chosen percentage while keeping the shape. Useful for oversized 3D scans, slow slicers and upload limits. Runs locally in your browser.
- Convert STL ASCII to Binary (and back)
Convert a text (ASCII) STL into the compact binary STL that slicers load faster, or the other way round for inspection. Binary files are typically 4–5× smaller.
- Scale / Resize an STL File
Resize a 3D model by a factor, to an exact target dimension, or fix a model that came out 25.4× too small or too big because of inch/millimeter confusion.
- Repair an STL File
Weld duplicate vertices, remove degenerate triangles, recompute normals and get a report of open and non-manifold edges before you slice. Basic repair for common export problems.
- STL File Info: Binary or ASCII, Triangle Count, Header
Inspect what is inside an STL file: encoding, header text, triangle count, bounding box and whether the mesh is closed. Handy before sending a file to a print service.