A simple but incredibly useful tool for anyone working in CAD. This 20mm × 20mm reference square is designed to be placed in a photo of an existing part, object, or space before importing the image into your CAD software. Once imported, simply scale the image until the square matches its real-world 20mm dimensions — your photo is now accurately scaled and ready to trace, measure, or design around.

Perfect for reverse engineering parts, designing custom brackets or enclosures, tracing organic shapes, or any situation where you need to work from a photograph with real-world accuracy.

Print one out, keep it in your toolbox or workspace, and never guess at scale again.

This is the first in a growing collection — additional reference sizes for various project types and scales will be added over time, so follow the profile to stay updated!