PrintableRuler.online
Printable Ruler
Need a ruler right now? Skip the store trip. Just choose your length, measurement unit, and paper size, then print. PrintableRuler.online creates a true-to-scale ruler you can use immediately. Every ruler comes with a built-in accuracy checker. Verify it prints perfectly before you cut. No guesswork. No wasted paper. Free. No sign-up. No downloads.
Any length, any unit
Standard 30cm and 12in rulers, or build a custom ruler from 1cm up to 300cm in centimeters, inches, or millimeters.
Long rulers, tiled automatically
Need a 1-metre ruler? We split it across multiple sheets with alignment marks so you can tape them into one long, accurate ruler.
Print accuracy checker
Most printers silently scale pages to "fit." Print our credit-card-sized test box first to confirm your printer is outputting true 1:1 scale.
No printer? Use the online ruler
Calibrate a ruler to your exact screen once, then measure directly on-screen in cm or inches — handy for laptops, tablets, and phones. Try the online ruler →
Custom Ruler Builder
Set your length, unit, and paper size below. The preview updates live and matches what will print — as long as your printer is set to 100% scale (see the accuracy checker below).
Preview is shown at true physical scale on screen only if your browser window isn't zoomed. The printed version will always be correct as long as printer scaling is set to 100% — see below.
Or grab a ready-made ruler
Prefer not to fiddle with settings? These common sizes are ready to print instantly.
Download a ready-made PDF ruler
No browser needed — these PDFs are built at exact physical scale (points, not screen pixels), so they print accurately straight from any PDF viewer as long as your print dialog is set to 100% scale / "Actual size" (not "Fit to page").
6 Inch Ruler
Single US Letter page, 1/16in detail.
12 Inch (1ft) Ruler
2-page US Letter, tape together — alignment marks included.
18 Inch (1 & 1/2 Ft) Ruler
3-page US Letter, tape together — alignment marks included.
15cm Ruler
Single US Letter page.
30cm Ruler
2-page US Letter, tape together — alignment marks included.
Full-Page A4 Ruler
Single A4 sheet, landscape, edge-to-edge cm/mm scale.
Full-Page US Letter Ruler
Single Letter sheet, landscape, edge-to-edge cm/mm scale.
Check your printer's accuracy
Before trusting any printed ruler — ours or anyone else's — confirm your printer isn't scaling the page. The box below is sized to exactly a standard credit/debit card: 85.6mm × 53.98mm.
85.6mm × 53.98mm
(3.370in × 2.125in)
After printing, hold a real credit card against the printed box. If it's off, open your printer's dialog and set Scale to 100% and turn off "Fit to page."
How to print a perfectly accurate ruler
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Run the accuracy check above
Confirms your printer settings are outputting true 1:1 scale before you rely on any measurement.
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Build or choose your ruler
Set the length, unit, and paper size in the builder, or pick a ready-made preset.
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Open the print dialog
Press the Print button, or use Ctrl+P / Cmd+P.
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Set scale to 100% and margins to none
Disable "Fit to printable area" or "Shrink to fit" — these are the #1 cause of inaccurate printed rulers.
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Print, cut, and (if tiled) tape sheets together
Cut along the outer edge and align the marked lines if your ruler spans multiple sheets.
About Printable Ruler
PrintableRuler.online exists because "I need a ruler and don't have one" is a more common problem than it should be. Instead of digging through a drawer or driving to a store, you can generate one here that's genuinely true-to-scale and print it in under a minute.
The core idea is simple but easy to get wrong: browsers and printers love to auto-scale pages to "fit," which quietly shrinks or stretches anything printed from them — including rulers. That's why every tool on this site is paired with the print accuracy checker above, so you can confirm your printer is outputting true 1:1 scale before you trust a single measurement. Rulers longer than one sheet are automatically tiled across multiple pages with alignment marks, so you can tape them into one continuous, accurate ruler. And if you're away from a printer entirely, the on-screen digital ruler can be calibrated to your exact display for quick measurements without paper at all.
Everything — the builder, the presets, the PDFs, the calibration — runs in your browser. Nothing you enter is uploaded or stored on a server, there's no account to create, and there's no cost. It's built for students, crafters, makers, and anyone who just needs an accurate measurement right now.
Frequently Asked Questions
How accurate is a ruler I print at home?
It's exactly as accurate as your printer's scaling setting. Every ruler here is generated at true physical size, so the only variable is whether your printer applies "Fit to page" or "Shrink to fit" — both of which silently resize the output. Run the print accuracy checker above first: if the printed test box measures 85.6mm × 53.98mm, your printer is set correctly and any ruler you print afterward will be accurate too.
Why does my printed ruler come out slightly short or long?
Almost always it's page scaling, not the ruler itself. Open your print dialog, set Scale to exactly 100% (sometimes labeled "Actual size"), and turn off any "Fit to printable area" option. Some printer drivers also apply their own default scaling separate from the browser's — check there too if the browser dialog already shows 100%.
Can I print a ruler longer than one sheet of paper?
Yes. Set a length longer than your paper size in the builder and it automatically splits the ruler across multiple sheets with alignment marks printed at each edge. Print all the sheets, trim along the outer edges, and line up the marks to tape them into one continuous ruler. For common long-ruler sizes, the ready-made 12in, 18in, and 30cm PDFs already have this tiling built in.
What's the difference between the on-screen builder and the PDF downloads?
The builder generates a ruler live in your browser based on the length, unit, and paper size you choose, and prints straight from that page. The PDFs are pre-built at fixed physical scale for a handful of common sizes (6in, 12in, 15cm, 30cm, and full-page A4/Letter) — useful if you want a file you can save, email, or reopen later without rebuilding it, or if your browser's print-to-PDF isn't behaving.
Does the online ruler work without printing anything?
Yes. The on-screen digital ruler lets you calibrate against a real object (a credit card, by default) once for your specific screen, then measure directly on the display afterward. It's a good option on a phone or laptop with no printer nearby, though a printed ruler is still more precise for anything you need to physically mark or cut.
Will the ruler print correctly on both A4 and US Letter paper?
Yes — pick the paper size that matches what's loaded in your printer before printing, since A4 and Letter have different dimensions and the layout adjusts to fit. If a ruler needs more sheets on one paper size than another, the tool will suggest switching to the size that fits it on a single page where possible.
Is any of this data saved or sent anywhere?
No. The ruler length, unit, paper size, and screen calibration you set all stay in your browser. Nothing is uploaded to a server or stored in an account, so there's no sign-up and no privacy tradeoff for using the tool.