Print checker
Margin, contrast, and module size.
OpenProof the print. Do not trust the screen alone.
Generate a symbol, flag a thin margin or a weak contrast, and print a sheet of real sizes.
Test sheet
Five real sizes to scan with a phone.
OpenPoster preview
Keep the quiet zone off the type and the trim.
OpenOn this device
The calculation stays in this browser. The worked example on the guide is written in HTML so the inputs and the result can be read without running the script.