Engineering
Explain symbols
GD&T frames, fits, threads, finishes and notes explained in plain words.
Callouts in plain words
Click a GD&T frame, a fit or a hole note: Explain says what it means.
- GD&T frames, fits, threads, finishes and notes explained in plain words
More in Engineering drawings
Tools that go with it.

Dual Viewer and Overlay
Two documents side by side, or one over the other to spot every change.
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Dimension Inspector
Read every dimension of a drawing, vector or scanned, and edit values in place.
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Auto-number CN balloons
Place numbered balloons on all dimensions in one click, filling gaps first.
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Drawing review
ASME Y14.5 checks plus engineering consistency: revisions, sheets, gear maths, keyways, parts list, notes against views.
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Change report
What changed between revisions in words, with the CN balloons carried over.
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Product map
Parts, assemblies and 3D models linked to their drawing pages.
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