How to use the clay shrinkage ruler
Set your clay body's shrinkage rate using the slider or type it directly. Choose the fired length you want, then select your paper size. Click Download print PDF and print at 100% / Actual Size—never "Fit to page."
After printing, measure the calibration bar printed at the bottom of each section. If it doesn't match 100 mm (or 4 in for imperial), adjust your printer's scale setting and re-print. A mismatched calibration bar means your ruler will be inaccurate.
Shrinkage rate calculator
If you don't know your clay body's shrinkage, use a test bar to measure it. Supplier figures are starting points only—your forming method, drying, and firing schedule all affect the final result.
Pottery ruler PDF and SVG formats
The PDF export tiles your ruler across A4 or Letter pages with 5 mm alignment overlaps. The SVG export produces a single continuous file at the exact physical length—useful for professional cutting plotters or for importing into other tools. Both contain a calibration bar.