Free tools
Tattoo size calculator and true-size print sheet
Direct answer
This tattoo size calculator converts a design size between centimetres and inches, shows it against a scaled placement reference, and prints a calibration ruler so you can confirm your printer is outputting at 100%. A 3-inch tattoo is 7.6 cm; a design that measures short on paper means scaling is on, and "Actual size" must be selected instead of "Fit to page".
Bigger than this placement reference — check it against the actual limb.
Print at 100% / "Actual size", then measure the bar with a ruler.
How this works, and what it will not do
Almost every "my stencil printed too small" problem is a print-scaling setting, not a design problem. Printer drivers default to shrink-to-fit so that nothing is clipped by the unprintable margin, which silently reduces a stencil by 3–6%. On a 15 cm design that is nearly a centimetre.
The calibration sheet below is the check: print it at 100%, measure the 10 cm bar with a ruler, and if it is short, scaling is on. Fix the setting before you print the stencil, not after you have transferred it.
The placement outlines are proportional references for judging relative scale, not anatomical measurements — bodies vary. The final check is always the printed stencil held against the actual limb.
Frequently asked questions
How big is a 3 inch tattoo in cm?
A 3-inch tattoo is 7.6 cm. One inch is exactly 2.54 cm, so multiply inches by 2.54 for centimetres, or divide centimetres by 2.54 for inches.
Why did my tattoo stencil print smaller than I set it?
Almost always print scaling. Printer dialogs default to "Fit to page" or "Shrink to fit", which reduces the page by a few percent to avoid the unprintable margin. Choose "Actual size" or set scale to 100%, then verify with the calibration bar.
What size should my first tattoo be?
Most first tattoos land between 5 and 12 cm (2–5 in). Below about 4 cm, fine detail closes up as the tattoo ages, so simpler designs hold up better at small sizes. Your artist will size it to the placement in person.
Does this send my measurements anywhere?
No. The calculator and the calibration sheet run entirely in your browser. Nothing is uploaded and nothing is stored.