A private STL viewer
MeshMath reads the STL directly in your browser with WebGL and three.js. Nothing is uploaded, so it is safe for client parts and unreleased designs, and it opens even large files in a second or two.
What it measures
Dimensions are the axis-aligned bounding box of the mesh in file units. Volume is the exact enclosed volume (signed tetrahedron method) and surface area is the sum of all triangle areas. The bed check tries the model in both XY orientations and tells you the largest scale that will fit.
Need to resize the model? Use the STL scale calculator. Want weight and cost? Try the STL weight calculator.
FAQ
How do I open an STL file without software?
Drop it onto this page. Any modern browser on Windows, Mac, Linux, Android or iOS can display it — no install or account needed.
Is my STL uploaded?
No. The file is read locally by JavaScript and never leaves your device.
What units does an STL use?
STL has no units. Nearly all files are in millimetres; if the size looks 25.4× too small, the file was exported in inches — switch the units selector.
Why does my model show holes or odd shading?
The mesh probably has flipped normals or isn't watertight. The viewer still measures it, but volume may be off; repair it in your slicer or a mesh tool before printing.
Recommended gear
- Digital calipers (150 mm) — Essential for tolerances, flow calibration and checking prints.
- Textured PEI build plate — Reliable adhesion and easy release; check your printer’s size.
Some links are affiliate links: if you buy through them MeshMath may earn a small commission at no extra cost to you. Picks are generic categories, not paid placements.
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