QR codes for print: size, contrast and the quiet zone

Size: about distance ÷ 10, minimum 2 cm. Shorter content gives bigger modules.
Quiet zone: four modules of clear space on every side. Don't let text or borders creep in.
Dark on light, high contrast. Colour is fine; low contrast isn't.
SVG for print. If it has to be PNG, 300 pixels per inch of printed width.
Proof on paper, at the real distance, with more than one phone.

A QR code on a screen is forgiving. The same code on a flyer, a menu or a shop window is not: the paper absorbs ink, the light is uneven, people stand at odd angles and nobody tries twice. Most failed print codes fail for one of five reasons, and all five are easy to avoid.

How big should a printed QR code be?

The rule of thumb used across the print trade is width ≈ scanning distance ÷ 10. A menu held at 30 cm needs a code about 3 cm wide. A poster read from 3 metres needs about 30 cm. It isn't part of any standard, and a sharp, well-lit code can do better, but it is a reliable starting point.

Two limits sit alongside it. First, don't go below 2 cm, even for things held close, because phone autofocus gets unreliable near the lens. Second, look at module size. A QR code is a grid of squares called modules, and its size in modules depends on how much you encode: 21 by 21 for the smallest code, up to 177 by 177 for the largest. Halve the content and you often drop several sizes. At the same printed width, fewer modules means bigger modules and easier scanning.

The size calculator builds your actual code, counts its modules and tells you the printed width, module size and export resolution.

The quiet zone is part of the code

The QR specification (ISO/IEC 18004) asks for a blank margin, the quiet zone, four modules wide on all four sides. Scanners use it to find where the code starts. Designers tend to trim it to save space or run a border, a photo or a line of text right up to the modules, and that is the single most common reason a printed code fails.

Our generator adds a four-module quiet zone to every download. When you place the code in a layout, treat that white box as part of the code: nothing goes inside it, including the edge of a coloured panel.

Contrast beats color

Scanners convert the image to light and dark and look for the pattern. That means:

Dark modules on a light background. Black on white is ideal, but navy, forest green or burgundy on white or cream work fine.
Avoid light-on-light and dark-on-dark. Pale grey on white, or navy on black, can look elegant and fail in a dim restaurant.
Be careful with inverted codes. Most phone cameras read light modules on a dark background, but some older scanner apps don't. Test before committing.
Keep backgrounds plain. Gradients, textures and photos behind the code add noise.

The generator warns you when the contrast between your two colours drops below 4:1 or when the code is inverted.

Logos and error correction

QR codes carry redundancy, so part of the code can be damaged or covered and still decode. There are four levels: L recovers about 7%, M about 15%, Q about 25% and H about 30%. Higher levels make the code denser. For plain print, M or Q is a good balance. If you put a logo in the middle, use H, keep the logo small (our generator caps it at about a fifth of the width) and never cover the three large corner squares.

File format and resolution

Send the printer an SVG. It is vector, so the edges stay perfectly sharp at any size and the printer can't accidentally blur it. If a system only accepts raster images, export a PNG at at least 300 pixels per inch of printed width, including the quiet zone. A 5 cm code with its margin is about 2.4 inches wide, so 720 pixels or more. Never enlarge a small PNG; the soft edges between modules confuse scanners.

Paper, finishes and placement

Matte over gloss. Glare from ceiling lights can wipe out half a glossy code. Matte or silk stock, and matte laminate, are safer.
Flat surfaces. Codes wrapped around bottles or tight curves distort. Keep them on the flattest panel.
Away from folds and trims. A fold through a code cracks modules; a trim can cut off the quiet zone.
At a comfortable height. On posters and signs, between chest and eye height. Nobody crouches to scan.
With a reason. A short line like "Scan for the menu" or "Join the guest Wi-Fi" next to the code tells people why they should bother.

Proof before you print the run

Print one copy on the actual stock if you can, or at least at actual size. Scan it with two different phones, ideally one iPhone and one Android, from the distance and angle people will really use, in the light of the place it will hang. Check that the link opens the right page and that the page works on mobile. Then order the run.

If the code points to a web page, consider pointing it at a page you control, so that a typo in the destination or a moved page doesn't mean reprinting. Our guide on static vs dynamic codes explains the options, and the print templates give you ready-made layouts that follow every rule above.

Sources

Questions

Can a QR code be colored?

Yes. Scanners look for contrast, not black specifically. Dark navy, deep green or burgundy on white or cream all scan well. Avoid light colors for the modules, and test inverted (light on dark) codes carefully because some scanner apps still struggle with them.

Does glossy paper cause problems?

It can. Overhead lights reflect off gloss and laminate, and the glare wipes out part of the code. Matte or silk finishes are safer for anything people scan indoors. If you must laminate, choose a matte laminate.

What's the smallest QR code that will scan?

Phones can read tiny codes in perfect conditions, but for print we treat 2 cm as the practical floor, with modules no smaller than about half a millimetre. Below that, older phones and dim rooms start failing.