STL measurement and scaling

STL Dimensions Checker

Find your model’s width, height and depth, interpret its design unit, and calculate a proportional scale for the size you want to print.

STL geometry is stored as unitless coordinates, so STL files do not reliably contain unit metadata. You choose how those coordinates should be interpreted after measurement.

Measure your STL

Upload an STL to measure its width, height and depth.

Choose STL file

Select a non-empty .stl file.

How STL sizing works

An STL records vertex coordinates but normally does not say whether a value of 50 means 50 millimetres, centimetres, metres or inches. Select the unit used by the design software, then use the conversions and proportional scale calculator above to prepare the intended print size.

What the results mean

Use the displayed unit conversion to confirm scale before slicing. Proportional scaling keeps the model shape intact, while the build-volume comparison checks the current dimensions against your printer.

FAQ

Do STL files have units?

No reliable unit metadata is embedded, so use the unit from your modelling software.

Can I convert millimetres to inches?

Yes. The checker converts the same measured coordinates for display without changing your source file.

Will it fit my printer?

Enter its usable build dimensions to compare it before slicing.

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