Measure

Distances, angles, radius, arc length, face area and the gap between two entities.

Measure works two ways, and the mode chips in the tool banner switch between them.

Points is freehand: click anywhere — on a model or the build plate — and each click extends a polyline. It reports every segment's length, the ΔX · ΔY · ΔZ of a lone segment, the interior angle at each corner, and the bearing of the first segment. Hold Shift to lock a point to an axis, and drag any placed point to adjust it.

Entities measures the model's own geometry, which is what you need for the numbers a point pair cannot express. Click an edge for its length — and if it is a circle or an arc, its diameter, radius and arc length. Click a face for its area and perimeter. Click a corner for its coordinates. Click a second entity of any kind and it adds the minimum distance between the two, drawn along the line it is actually measured on.

A round edge reports the ideal circle it was built from, not the sum of the little straight chords the mesh is made of — those run about half a percent short on a typical hole, which matters when you are printing to a fit. When an edge is straight or simply not round, no radius is quoted at all rather than a meaningless one.

Two things worth knowing. A curved wall — the side of a cylinder — is not a single face: it is built from flat facets, so a click measures the highlighted facet, and the highlight always shows exactly what the numbers describe. And a very dense imported mesh offers no edges or corners to grab, because finding them on hundreds of thousands of triangles would stall the viewport.

1. Activate Measure.
2. Points mode: click a first point, then a second — keep clicking to extend a polyline.
3. Entities mode: click an edge, face or corner to measure it; click a second one for the distance between them.
4. Press Esc to clear the selection, and again to finish.