Printable ruler

Print at 100%, then calibrate so it's truly to scale — handy for checking a card, a bleed, or an outline.

Calibration — print the page, measure the line below with a real ruler, enter the length you got (mm)

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Credit-card reference (85.60 × 53.98 mm):

How to use

Print the page at 100% (no 'fit to page').
Measure the blue 100 mm line with a real ruler.
Enter the length you measured to calibrate the scale.
Lay a bank card on the outline to sanity-check.

FAQ

How do I get an accurate ruler?

Print this page at 100% (no "fit to page"), measure the 100 mm line with a real ruler, then enter the actual length in the calibration box. The ruler rescales so it prints true.

Why is my printed ruler the wrong size?

Browsers and PDF viewers default to "fit to page", which shrinks everything by 4–6%. The calibration step corrects for that.

What is the credit-card reference for?

Every bank card is an ISO/IEC 7810 ID-1 card — 85.60 × 53.98 mm. Lay a real card on the outline to sanity-check the scale.