Exact measurements in mm

Hi, i just started using sketchup pro 2019. When I use the tape measure tool, it is not telling me the exact measurements, for example its is saying ~15mm, not 14.7mm.

It is possible to make it say the exact measurement?

Thank you.

Go to Window/Model info/Units and set the precision there.

wow, thank you! you’d think if you’re working in mm that it wouldn’t just give you round measurements as standard.

It depends on the template you chose to work with.

And it’s not advisable to work in mm, sketchup fails to form tiny edges when it gets down in the fractions of mm. If you are designing for 3d printing you can work in meters and export as mm.


Thank you to you both for the help and the useful info!

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Have a look here for a fuller explanation.

I work with exact measurements in mm up to 3 decimal points all the time with absolutely no issues. In woodworking the majority of European hardware works on the 32 mm system.

If I am working with a 5 mm drill bit then it is exactly 5 mm NOT 0.1968" which is ONLY its imperial approximation. If you use the calculator and convert you get this 0.1968503937007874015748031496063

Of course under the hood (unlike most CAD systems), Sketchup stores data in decimal inches. However - if you need to work in mm then work in mm.

I support users all over the world and move between inches and mm all the time without any real issues.

For instance I’ve written this out as a polyline DXF file (mine) and then imported it back into SU for testing. This is what I get using mm. BTW - I reduce the number of segments since they are only for rendering. My DXF retains perfect arc information AND uses polylines to guarantee proper control of CNC machinery.

I never said you can’t draw edges that small, but try forming faces consistently.

Works for me !!!

I use Ruby and a bunch of specific strategies and I’ve not see any issue !!! BTW - the 8 is drawn that way ONLY for rendering.

The CNC sees it as perfect geometry.
Here is a 2 with an underline and this part has JUST come out of a CNC machine.

Using SU import you get this. Which has LOST arc information and converted everything to small line segments


My DXF import gets this which has retained all proper arc information.


I’m afraid you’re missing the point.
But if it works for you that is great.

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I’m not missing the point - I just choose to solve problems a different way. I’ve been programming computers since the beginning of DOS. I’ve worked on things like S-Squared memory where you read and write memory locations 32 bytes at a time. I’ve programmed with Assembler for firmware etc.

No I’m not missing the point. mm is just fine - IF YOU KNOW how to work with it properly.

Ok. Repeat my gif and form a curved face.

Here is how I get what I want. The math works perfectly.


I’m talking about the arced face that is failing.

Then you are missing my point. The point I made is that I can move between inches and mm without any difficulty for what I need to do - so don’t dismiss mm so quickly.

Before I even consider what you are suggesting give me a real use case.

When it comes to Cabinets (my industry) I don’t have a use case for what you are suggesting. So give me one.

3d printing, designing organic shapes that are complex and less than 100mm cube. Which is what I suggested when I mentioned working at a larger scale to avoid the tiny face issue that plagues many many users on the forum.

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The point isn’t that SketchUp can’t convert precisely between mm and inches (it can to like 11 decimals or something) but that it struggles to form tiny faces. You can draw to mm in SketchUp, and here in Sweden all architectural drawings are in millimeters. What doesn’t work is drawing faces with sides shorter than about a tenth of an inch. That is why it is recommended not to draw at full scale when 3D printing small high fidelity objects, e.g. jewelry, but to draw at e.g. scale 1000:1. SketchUp was originally designed for architecture and perhaps wood working, and was programmed to for whatever reason not form such tiny faces.


Box - this is what you said and this is what I was commenting about.

And it’s not advisable to work in mm, sketchup fails to form tiny edges when it gets down in the fractions of mm. If you are designing for 3d printing you can work in meters and export as mm.

I took exception to you saying DO NOT WORK IN mm

The point is - the units are not important. The fact that you are trying to do things really really tiny is what is important.