Keep the coordinate frame visible
Axis-aligned extents depend on orientation. Record the source or assembly frame rather than silently finding a different one. A compact bounding box is not automatically a machining blank.
CADProps · CAD tools
CAD Measurement Online: STEP Dimensions & Distances
Check STEP bounding dimensions in source coordinates and pick approximate point distances in an interactive 3D viewer. Source units are normalized to millimetres.
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Temporary workspaceCAD processingBefore you use the result
Know what you are looking at.
For a quick fit check, start with overall size and the coordinate frame. For a specific feature, name the geometry being measured; a bounding box is not a drawing dimension.
Measure from the right data
A screen pick should identify the intended geometry where the reader supports it. If the result comes from a mesh approximation, label the method. More decimal places do not make a preview measurement more reliable.
Keep tolerances separate
The model reports its current geometry. Manufacturing acceptance comes from the agreed specification or drawing. A display or comparison threshold is not a drawing tolerance.
A reproducible example
Generated STEP block: 20 × 30 × 40 mm, surface area 5,200 mm² and volume 24,000 mm³. At density 2.7 g/cm³ the calculated mass is 64.8 g. These values describe the synthetic block, not the default bearing sample.
Repository-generated samples are synthetic test models. Verify your own model's units and geometry before using results.
Questions about this task
Know the limits.
What do the three dimensions mean?
They are an axis-aligned bounding box in source coordinates, not an automatically oriented minimum box.
Which measurements are approximate?
Picked point distances use the display mesh. Supported B-Rep edge and diameter measurements use original CAD geometry.
Are my files uploaded?
Selecting a file starts temporary server processing. Access is limited to your guest session. The entry shows configured retention and files can be deleted earlier.
Related reading
Checks that help with this file.
MeasurementCAD File Size vs Part Weight: Why MB Does Not Mean Mass
Megabytes describe storage. Grams describe mass. Here is why a large file can represent a light part, and what you need for a useful mass estimate.
Read the guide →
Versions & reviewCompare CAD Revisions: Geometry and Property Checks
Use fixed versions, explicit units and a deliberate alignment method before interpreting overlays or property differences.
Read the guide →MeasurementMeasure STEP Files Online: Dimensions, Distances & Units
Read a CAD model without confusing bounding-box dimensions, selected geometry measurements and drawing tolerances.
Read the guide →