Here's an easy way to measure your head for the purpose of scaling 3D models to fit, or fabricating masks to propoerly fit your head.

Here's a link to 3D printable cosplay calipers I modelled. You can also simply cut out similar shapes from cardboard to use as calipers.

https://www.thingiverse.com/thing:554...

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Credits: Written by Popovic Recorded and produced by Popovic / Vodovoz