Drawing a circle using diameter

I take it that there isn’t a way to draw circles using a diameter rather than a radius?
I have a circle of diameter 17/64 and it would really be nice not to have to do the math to figure
out the radius.

You are correct. But that isn’t really much of a math problem. Especially given the vcb will do the math for you.

Draw an edge the desired diameter then use its midpoint as the center and drag the circle tool out to an end of the edge. Let SketchUp do the division!

or begin the circle and type the desired diameter/2 (if it’s whole numbers or decimals) I think it would serve to complicate the UI to have options in dims and entity info to choose display of radius or diameter.

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Be aware that SketchUp does not actually support arithmetic in the measurements box, the seeming support is a side effect of handling fractions. The numerator must be a whole number.

Yeah…two denominators doesnt work that well.
Not to mention in a template in 64ths a diameter of 17/64 would display a radius of approximate values.

Or, draw the circle the required diameter then use the Scale tool to reduce the size to 0.5.

If you do this often, there is an extension that would help: Extension | SketchUp Extension Warehouse

Thank you. All great suggestions. Maybe at some point an r or a d suffix or prefix could be incorporated into the SketchUp app.

If your diameter is really 17/64ths you might run into the small face issue.

That’s a great and rather elegant solution.

Like this?


I too find it a PITA to draw circles. Most always i put in the diameter and then get a circle twice as big, delete then redraw. Don’t most people think of circles in the terms of diameter and arc’s or fillets in terms of radius? I wish it would also put a point or tick at the center to snap to. I frequently have a very hard time finding the center of circles or arcs.

I’ve never really found it all that difficult to enter the radii of circles.

Inferencing is available to find and snap to the centers of circles and arcs. You can also place a guidepoint at the center if you need it.