There is a rule of thumb that has survived a lot of bad posters: the code should be about a tenth as wide as the distance someone will scan it from. A card in the hand, 15–20 cm away, can live at 20 mm. A poster scanned from a metre away wants something closer to 10 cm. Denso Wave, the company that invented the symbology, has published that 10:1 ratio for years. Treat it as a starting point, not a guarantee.
The guarantee comes from a test print. Phones, glare, and a URL that ballooned the symbol to version 12 will all argue with the chart.
A size chart you can brief a designer with
Widths below include the quiet zone, the blank margin around the modules. If your layout crops that margin, the chart no longer applies.
| Where it sits | Typical scan distance | Minimum width |
|---|---|---|
| Business card, held | 10–15 cm | 20 mm |
| Menu, tent card, packaging in the hand | 25–30 cm | 30 mm |
| Counter, shelf talker | 50 cm | 50 mm |
| A4 poster, people stop in front | 1 m | 10 cm |
| Shop window, banner | 1.5–2 m | 15–20 cm |
Round up when any of these are true: the link is long, you embedded a logo, error correction is set to H, the stock is uncoated or corrugated, or the code sits behind glass. A short menu URL on a matte tent card can sit on the low end. A campaign URL with four UTM parameters, a logo, and gloss laminate should not.
“Make the QR 300 pixels” is how a 25 mm code ends up on an A3 poster. At 300 dpi, 300 pixels is one inch. Tell the studio the physical width, quiet zone included, and send an SVG.
The check the chart does not do
A QR symbol is a grid. Version 1 is 21 by 21 modules. Each higher version adds 4 modules a side, up to version 40. A short URL often lands around version 3 to 5. Add a long query string, high error correction, or a logo and you can jump several versions without the printed width changing. The squares just get smaller. That is when scans start failing even though the code “looks big enough” on the artboard.
Keep each module at or above about 0.4 mm on paper. Below that, ink gain and a tired phone camera start tossing a coin.
Quick maths. A version 5 symbol is 37 modules. Add the standard quiet zone of 4 modules per side and the full mark is 45 modules across. Printed at 30 mm:
30 ÷ 45 = 0.67 mm per module. Fine for a menu.
Same artwork, but the tracking link pushed it to version 10 (57 modules, 65 across with the quiet zone) and someone scaled it down to 22 mm to fit a column:
22 ÷ 65 = 0.34 mm. That is the file you will be reprinting.
You do not need to memorise versions. Export the code, drop it into the layout at the real size, and zoom until one module is measurable. Or scan a proof. The proof is faster and catches problems the maths misses, like a cream background.
The quiet zone is not padding you can steal
The spec wants four modules of empty space on every side. No border, no type, no pattern that touches the finder squares. Designers steal it constantly because the code looks like it has too much air next to a tight logo lockup.
If the generator’s margin is already the quiet zone, do not put the SVG in a box that clips it. If you set the margin to zero because you want to draw your own frame, leave the frame at least four modules out. On a 37-module symbol that is roughly 10% of the width on each side. It feels generous. It is the difference between a scan and a camera that hunts and gives up.
The surface changes the size
A flat, matte menu is the easy case. Other jobs need more width than the chart suggests.
- Gloss laminate and windows. The overhead lights blow out a band of modules. Bigger helps, but moving the code off the glass or using a matte film helps more. Test at the time of day the shop is actually open.
- Curved packaging. A code wrapped around a bottle distorts. Keep it on a flat panel, and keep the data short so the grid is coarser.
- Corrugated board and kraft. The flutes and the fibres eat small modules. Go up a size and stay with black on a light panel, not brown ink on brown board.
- Fabric and embroidery. If you cannot see a crisp square, neither can the camera. This is usually the wrong medium.
For the colour and logo decisions that interact with all of this, the design rules are the other half of the brief. Size will not save a low-contrast mark.
Short links print smaller
https://cafe.example/menu and a 180-character campaign URL are not the same symbol. The second one carries more modules, so it needs more paper to hit the same module size. If the piece is small (a collar label, a business card, a jar lid) shorten the path before you shrink the artwork.
That does not mean a mystery short domain you do not own. A short path on your site, https://cafe.example/m, keeps the code coarse and still points somewhere you control. How to do that without renting a redirect is covered in static versus dynamic codes.
Proof it at the real distance
Screen proofs lie. PDF zoom lies. The useful test is boring:
- Print at 100% on the stock you will use, or stick a same-size proof on the actual window.
- Scan with an iPhone and an Android. One of them will be a phone that is a few years old, because that is what half the room is holding.
- Stand where the customer stands. Not closer, to “help it along”.
- Try the worst light you expect: evening window, dim restaurant, direct sun.
- If it fails, make it bigger or make the data shorter. Do not “fix” it by adding a heavier logo.
Questions that come up in production
What is the smallest QR code I can print?
For a short link held in the hand, about 20 mm including the quiet zone is a sensible floor. Go larger if the URL is long, error correction is high, or a logo sits in the middle. Keep each module at or above 0.4 mm, and scan a real proof before you approve the run.
Does a 300 pixel QR code print large enough?
Pixels are not a print size. At 300 dpi, 300 pixels is about 25 mm, which is a business-card code, not a poster. Export SVG for print. If the printer insists on a raster, build the PNG at the physical width times 300 dpi, quiet zone included.
Should the quiet zone be included in the size?
Yes. If you tell the printer “30 mm” and the margin gets cropped because it looked like empty space, you have a smaller symbol than you tested. Specify the width of the whole mark.
Can I put one code on a billboard?
Only if drivers are not the audience. A code sized for 10 metres is a metre wide, and nobody should be scanning from a moving lane anyway. Billboards are for a short URL humans can remember, or for people standing still in front of a placement you have actually measured.
Related: design rules that survive the printer, the campaign guide, and UTM links, which are a common reason a code gets denser than the layout allows.
Export the size you will actually print.
Set the resolution, leave a real margin, and download an SVG. The code is built in your browser.
Create your QR code