What Size Should a QR Code Be? Minimum Print Sizes Worked Out

Make your QR codeDownload the QR code print size chart (PDF)

Why there is no single minimum size

A QR code is a grid of small squares called modules. The smallest QR code, version 1, is 21 modules wide, and each version adds 4 modules per side, up to version 40 at 177 modules, according to Denso Wave's page on QR code versions. The more you put in the code, the higher the version and the more modules it needs.

A phone has to see each module clearly. So the printed size of a code is really the number of modules multiplied by how big each module is printed. Two codes printed 2 cm wide can behave very differently: a short link might have modules half a millimetre across, while a full contact card squeezed into the same space has modules a third that size.

On top of the code itself, the standard asks for a clear border. Denso Wave's guidance says a QR code requires a four-module wide margin at all sides, so the space you need is the code plus 8 modules.

How many modules your code has

We generated four typical payloads with the same QR library the free QR code generator uses and counted the modules at each error correction level. Error correction is the spare data that lets a scratched or partly covered code still scan; M is the default, and adding a logo switches the code to H.

The full contact card with a logo has more than three times as many modules across as the short link. Printed at the same width, each of its modules is less than a third the size. That is why a generic "2 cm minimum" works for one code and fails for another.

You do not need to guess your own count. Once your code is ready, the generator says "Ready: 33×33 modules, error correction M" (or whatever yours is) underneath the preview.

Work out the size, step by step

1. Shorten what the code holds

Every character costs modules. Use the shortest web address that works: the page itself rather than a long link with tracking on it, unless you need the tracking. If you do want UTM tags, keep the values short (qr rather than qr_code_spring_flyer).

2. Read the module count

Make the code and note the count under the preview.

3. Add the white border

Add 8 modules, four on each side. In the generator, the "Standard" white border is exactly four modules and is the one to use for print. "Thin" is two modules and is meant for screens and tight layouts where the background around the code is already plain and light.

4. Choose a module size for the distance

A common rule of thumb is that a code should be about a tenth as wide as the distance it is scanned from: about 3 cm for a business card held 30 cm away, 10 cm for a poster scanned from a metre, 20 cm for a window read from two metres. As a floor for anything held in the hand, keep each module at least 0.5 mm across. These are working rules, not standards, so step 5 matters.

Printer resolution matters too. Denso Wave's page on module size and printers recommends that each module be at least 4 printer dots across for stable reading; on a 600 dpi office printer that is about 0.17 mm, so any office printer can print a 0.5 mm module cleanly.

5. Multiply and print a test

Total modules times module size gives the width. A 33-module Wi-Fi code plus its border is 41 modules; at 0.5 mm that is 20.5 mm, a little over 2 cm. Print one copy at the final size on the final paper and scan it from the real distance with two phones. The chart in this post's PDF has the widths already worked out.

Codes on screens and slides

The same logic applies on a screen, measured in pixels instead of millimetres. A code on a slide at the back of a meeting room needs to be large on the projected image, not just in the file; a code that fills a sixth of the slide's height is a reasonable start for a small room, and more for a hall. On a website, remember that most visitors are already on their phone and cannot scan their own screen, so a QR code there is for desktop visitors only and a plain link should sit next to it.

For screens, the PNG is the right download. Choose 1024 pixels for slides and documents and let the software scale it down; scaling a small PNG up makes the edges blur, which some cameras struggle with.

PNG or SVG for print?

For a print shop or a design tool such as Canva or Illustrator, download the SVG. It is drawn as shapes rather than pixels, so it stays sharp at any size. For an office printer or a Word document, the PNG at 2048 pixels is plenty: even printed 10 cm wide, that is over 500 pixels per inch.

Whichever you use, do not stretch the code in only one direction, do not crop the white border when trimming, and keep it dark on a light background. If a printed code is the right size and still will not scan, our troubleshooting guide covers the other causes, and the business card guide deals with the tightest space most people print a code in. If you need to change where a code points after printing, that is what dynamic codes in Fynl's paid plans are for; size them the same way.

The QR code generator is one of several no-sign-up tools on our free tools page, including a UTM builder for tagging the links you put in codes and a Google review link generator.

Questions people also ask

Sources

• DENSO WAVE — Information capacity and versions of QR Code
• DENSO WAVE — Points for generating QR Code (quiet zone)
• DENSO WAVE — Module size and printer