Nine times out of ten it’s the print dialog: choose Actual size / 100%, untick any “fit”, “shrink” or “scale to fit” option, turn off borderless printing, and make sure the paper size matches the paper in the tray. Then measure the test square again.
1. “Fit to page” or “Shrink oversized pages”
The most common cause by far. Printers can’t print to the very edge, so many dialogs shrink the page to fit the printable area – typically by 3–6%. On a sewing pattern that’s a whole size.
- Adobe Reader / Acrobat: Page Sizing & Handling → Actual size.
- Chrome / Edge: More settings → Scale → Default or Custom 100. Not “Fit to printable area”.
- Mac Preview: Scale 100%; under Paper Handling, untick Scale to fit paper size.
- Windows Photos / image viewers: these usually fit to page – print the PDF from TrueScale Print instead.
2. Borderless printing
Borderless mode slightly enlarges the page so ink reaches the edges. It’s great for photos and bad for templates. Turn it off in the printer’s settings.
3. A4 vs. US Letter mismatch
A4 is narrower and taller than Letter. If a file made for A4 is printed on Letter (or the other way round) with any fitting on, it gets scaled. In TrueScale Print choose the paper you actually have, and make sure the print dialog uses the same.
4. The file itself isn’t at 1:1
A screenshot, phone photo or CAD export with the wrong scale has no true size. Use Calibrate on a known dimension – or on the pattern’s own test square – so the whole file is scaled correctly.
5. The printer is slightly off
Even with everything right, printers vary by a fraction of a percent, and some are consistently a little short in one direction. If your square is consistently off by a small amount, compensate: calibrate the file so the test square comes out right on your printer, or adjust Scale vs. native by the error (e.g. 101% for a 1% short print).
6. You measured with a tape measure
Soft tape measures stretch and have thick ends. Measure the test square with a steel rule or a quilting ruler, and paper flat on the table.
Re-print with the right settings
Open TrueScale PrintFAQ
Why is my printed pattern smaller than it should be?
Almost always because the print dialog is set to Fit to page, Shrink oversized pages or Scale to fit. Choose Actual size or 100% and print again.
My test square is 4.8 cm instead of 5 cm. What do I do?
Check the print dialog is at Actual size or 100% and borderless printing is off. If it is still off, calibrate the file against the test square or set Scale vs. native to compensate.
Does A4 vs Letter matter?
Only if something is scaling the page to fit. Choose the paper size you actually have in TrueScale Print and in the print dialog.