Miniature Scale Lab

Printable scale ruler

Make a ruler that reads real-world sizes straight off a model or plan. Pick a scale, choose metric or imperial, then download a vector PDF or SVG sized for A4 or US Letter.

The on-screen preview is not true size. Screens don't report their real pixel density, so use the printed copy for measuring.

Printing it accurately

  1. Open the PDF and print with the scale set to 100% or Actual size. Turn off "Fit to page", "Shrink oversized pages" and "Scale to fit". The PDF asks viewers not to rescale it, but some still do.
  2. Print in landscape. The page is laid out landscape with 12 mm margins, which suits most home printers.
  3. Measure the 100 mm and 4 inch calibration lines with a steel rule, or lay a bank card on the outline. ISO/IEC 7810 cards are 85.60 × 53.98 mm.
  4. If the 100 mm line prints as 97 mm, for example, your printer applied a 97% scale. Fix the setting and print again rather than correcting by hand.

Even at 100%, paper can stretch and printers can be off by a few tenths of a percent. That's fine for dioramas and scratch-building, but don't use a paper ruler where tolerances are tight. Laminate it or glue it to card so it stays flat.

How the ticks are chosen

The generator picks the smallest "round" real-world step (1, 2 or 5 × a power of ten in metric; ⅛ in, ¼ in, ½ in, 1 in, 3 in, 6 in, 1 ft and up in imperial) whose ticks land at least 0.8 mm apart on paper, so they stay readable. Major ticks are labelled in real-world units. At 1:35 metric, for example, each small tick is 5 cm real (1.43 mm on paper) and each labelled tick is 50 cm. At 1:48 imperial, each labelled tick is one real foot, which is exactly ¼ inch on paper.

The files are drawn in millimetres. The SVG declares its width and height in mm, and the PDF page is in points (1 pt = 1/72 in), so A4 is 841.89 × 595.28 pt. Our automated tests read those values and every tick position back out of the exported files. See methodology and tests.

Not sure which scale to print? Use the converter, or see how sizes differ on compare scales. There's more on paper accuracy in printing accurate scale rulers.