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Pattern Print Scale Calculator

When a PDF pattern test square prints a little too small or too large, every seam and notch is affected. Measure the square you printed and this calculator gives you the exact percentage to use next time.

It takes seconds, works in centimetres or fractional inches and tells you when the result is already within a practical sewing tolerance. Reprint one test page, check it again and avoid wasting paper—or cutting the wrong size.

Reprint at104.2%
Expected10 cm
Measured9.6 cm
Scale error-4.0%
Current printOutside tolerance

Turn off “Fit to page”. Enter 104.2% as the custom print scale, reprint only the test page, and measure again.

How to use it

A clear result in five steps

  1. 1Print only the test page at Actual Size.
  2. 2Measure the printed test square.
  3. 3Enter expected and measured sizes.
  4. 4Reprint at the calculated custom percentage.
  5. 5Measure again before printing every page.
Method

The maths, without the mystery

Corrected print scale = expected size ÷ measured size × 100. A result within ±1% is reported as within tolerance, but precision-critical patterns should be checked again.

Questions

Frequently asked questions

Should Fit to page be enabled?

No. Disable page fitting and automatic scaling.

Can printers still vary?

Yes. Always measure the second test print.

Does this alter the PDF?

No. It only calculates the percentage for the print dialog.