How big should a QR code be when printed?
A QR code that is too small is the most common reason a printed code “doesn’t work”. The good news: picking the right size is not hard once you know the two things that matter, how far away people will be and how dense the pattern is. This guide gives you a rule of thumb, a table of typical sizes, and a short checklist to run before you print.
The quick answer
- For anything held in the hand (business cards, flyers, labels): at least 2 to 3 cm (about 0.8 to 1.2 inches) wide.
- For table cards and menus: 3 to 5 cm.
- For posters and signs: use the distance rule below. Divide the scanning distance by 10.
If your code is artistic (a photo QR code like the ones QRPetal makes), add a little more, roughly 20 to 30% extra, because the photo takes away some of the contrast a plain code would have.
The distance rule of thumb
A widely used rule is that a QR code can be scanned comfortably from about ten times its width. Turn it around and you get the size you need:
Code width ≈ scanning distance ÷ 10
| Where people scan it | Typical distance | Suggested width |
|---|---|---|
| Business card, label, ticket | 15 to 25 cm | 2 to 3 cm |
| Menu or table card | 30 to 40 cm | 3 to 5 cm |
| Flyer or brochure | 30 cm | 3 cm or more |
| Shop window | 1 m | 10 cm |
| A4 or letter poster on a wall | 1 to 2 m | 10 to 20 cm |
| Yard sign or banner | 3 m | 30 cm |
| Large banner across a room | 5 m | 50 cm |
This is a rule of thumb, not a law. Modern phone cameras are good, and many will read a code from further away. But people do not like walking up to a poster and crouching, so it is better to err on the large side.
Why density matters as much as size
A QR code is a grid of small squares called modules. The more text you put inside, the more modules the grid needs. The smallest QR code (version 1) is 21 × 21 modules; each version adds 4 modules per side, up to version 40 at 177 × 177.
What a phone actually has to see is each module, not the whole code. So a long web address squeezed into a 2 cm code gives tiny modules that are hard to print and hard to read, while a short address in the same 2 cm gives big, friendly modules.
A quick example. A short link fits in version 6, which is 41 modules wide. At 3 cm wide, each module is about 0.7 mm. The same 3 cm code holding a long tracking link might need version 12 (65 modules), where each module shrinks to under 0.5 mm. Same printed size, much harder to scan.
How to keep density low:
- Use a short web address. Remove tracking parameters you do not need.
- Use an editable (dynamic) code. It always holds a short link, whatever your real address is. Read more in dynamic vs static QR codes.
- Put less text in the code and more on the page it opens.
Do not forget the quiet zone
Around every QR code there must be a plain, light margin called the quiet zone. The QR standard asks for 4 modules on each side. Readers use this empty frame to find where the code starts and ends.
Designers often trim it to save space, or run a border or background photo right up to the code. That is one of the most common reasons a well-sized code still fails. When you measure your code’s width, measure the pattern itself, and keep the quiet zone extra.
How many pixels do you need?
For print, the usual target is 300 dots per inch (dpi). To work out the pixel width you need:
Pixels = width in cm ÷ 2.54 × 300
| Printed width | Pixels at 300 dpi |
|---|---|
| 2.5 cm (1 inch) | 300 px |
| 3 cm | about 355 px |
| 5 cm | about 590 px |
| 10 cm | about 1,180 px |
| 20 cm | about 2,360 px |
| 30 cm | about 3,540 px |
Large posters and signs are seen from further away, so 150 dpi is usually fine for them, which halves the pixels you need. A QR code has hard edges, so never enlarge a small image in an editor: that makes blurry module edges. Download the size you need instead, or use a print PDF when your tool offers one.
Artistic and photo QR codes
Photo QR codes trade some contrast for beauty. In a QRPetal code, parts of each module show your photo, and only small black or white marks carry the signal where the photo does not already. That is why we check every code with two different QR readers and give it a score before you download it.
For printing, that means:
- Give artistic codes more room: 20 to 30% larger than a plain code at the same distance is a good start.
- The more photo you show, the bigger the code should be. For small prints, move the style towards Easier to scan.
- A calm, high-contrast photo reads better than a busy, low-contrast one.
Paper, ink and light
Size is not the only thing that decides whether a code scans:
- Contrast: dark code on a light background is safest. Light-on-dark codes and pale colours fail on some readers.
- Finish: glossy paper and lamination reflect lights into the camera. Matte is more reliable.
- Surface: codes on curved bottles, folded paper or fabric get distorted. Keep them on flat areas, and smaller relative to the curve.
- Light: a code in a dim bar or bright sunlight is harder to read. If you know the lighting will be poor, print bigger.
A checklist before you print
- Decide the scanning distance and use the ÷ 10 rule.
- Keep the content short (or use an editable code).
- Keep the quiet zone clear on all four sides.
- Export at the right resolution for your size.
- Print one test copy on the real material.
- Scan it with two different phones from the real distance, in the real light.
- Only then print the whole run.
Getting the size right costs nothing, and a code that scans on the first try is the difference between a customer opening your menu and a customer giving up. If you want to see how different sizes and styles behave, make a free QR code and test it on paper.