3D Quality Tools

InspectMesh

Free STL Tools for 3D Printing

InspectMesh checks STL files before slicing or printing, so you can understand mesh health, size and complexity before committing material and time.

STL tools

STL Quality Checker

Find common mesh problems before printing, including open edges, non-manifold geometry, duplicate triangles and orientation issues.

Check STL quality

STL Watertight Checker

Check whether an STL has a closed surface, open edges or possible holes.

Check watertightness

STL Manifold Checker

Check whether an STL is closed and manifold, with clear counts for open edges, non-manifold edges and separate shells.

Check STL topology

STL Triangle Counter

Count triangles and understand mesh complexity before slicing or sharing.

Count STL triangles

STL Dimensions Checker

Measure an STL, convert units, calculate proportional scaling and check whether it fits your printer.

Measure an STL file

STL Volume Calculator

Calculate your model’s volume, convert units and estimate approximate material weight.

Calculate STL volume

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Which tool do I need?

STL tool FAQ

What is an STL file?

An STL describes a model surface as a set of triangles. It is common in 3D printing, but it does not reliably store design units.

Should I check an STL before slicing?

Yes. Open edges, non-manifold geometry and unexpected scale can lead to confusing slicer results.

Does a clean check guarantee a successful print?

No. Printer calibration, supports, material and slicer settings still affect the physical result.