QR code size calculator
The distance people scan from decides the smallest a code can be printed. This does the arithmetic, including the allowance a logo needs.
How big should a QR code be for a poster?
A QR code on a poster should be at least 3.6 inches (9 cm) wide if people scan it from 3 feet away. The rule is a 10:1 ratio: divide the scanning distance by ten to get the minimum code width. A billboard read from 30 feet needs a 3-foot code. Add 20% for a code carrying a logo.
Size it for what the code actually holds
The 10:1 rule assumes a short payload. A contact card is a much denser code and needs more width at the same distance, which the rule gives no hint of.
Why the 10:1 ratio works
A camera has to resolve individual modules, the small squares that make up the pattern. Phone sensors and autofocus vary, but at roughly a tenth of the viewing distance a code presents each module at enough pixels for reliable decoding, with margin for motion, angle and imperfect light. The ratio is a floor, not a target: printing larger is nearly always cheaper than a reprint.
Minimum QR code size by print type
| Print type | Typical scanning distance | Minimum width |
|---|---|---|
| Business card | 6 in / 15 cm | 0.6 in / 1.5 cm |
| Restaurant menu or table tent | 12 in / 30 cm | 1.2 in / 3 cm |
| Product packaging | 12-18 in / 30-45 cm | 1.2-1.8 in / 3-4.5 cm |
| Flyer or A4 poster | 3 ft / 1 m | 3.6 in / 9 cm |
| Retail window | 6 ft / 2 m | 7.2 in / 18 cm |
| Trade-show banner | 10 ft / 3 m | 12 in / 30 cm |
| Billboard | 30 ft / 9 m | 36 in / 90 cm |
Every row is the ratio, nothing else, which is why the table and the calculator above never disagree. One floor the ratio does not know about: below roughly 0.8 in / 2 cm, ink spread on uncoated stock starts merging modules whatever the arithmetic says, so treat that as the practical minimum for anything printed on paper.
What breaks scanning at small sizes
- Ink spread. On uncoated stock, ink bleeds into the white modules and merges them. Print small codes at higher error correction.
- A long URL. More data means more modules in the same width, so each module gets smaller. A short link keeps the pattern coarse. This is a real reason to encode a short link rather than the destination.
- Cropped quiet zone. Designers trim the white margin to make a code fit. Scanners then cannot locate the pattern at all.
- Low contrast. A brand-coloured code on a brand-coloured background can look fine on screen and fail in a dim restaurant.
What resolution should a QR code be for print?
Print a QR code from a vector file (SVG, EPS or PDF) and resolution stops being a question, because vector has none. If you must use a raster image, export it at 300 DPI at the final printed width: a 3.6 in code needs to be 1,080 pixels wide. Anything scaled up from a smaller PNG softens the module edges, and soft edges are what a scanner fails on.
This is the difference between a low-resolution code and a small one, and they fail for different reasons. A small code runs out of physical space for each module. A low-resolution code has enough space and blurry boundaries inside it, which is worse, because it looks fine in the artwork at 25% zoom and only falls apart on paper. Klip renders every code as SVG for exactly this reason; the PNG is there for the surfaces that cannot take vector.
| Printed width | Pixels at 300 DPI | Pixels at 600 DPI |
|---|---|---|
| 0.8 in / 2 cm (business card) | 240 px | 480 px |
| 1.2 in / 3 cm (menu, table tent) | 360 px | 720 px |
| 3.6 in / 9 cm (A4 poster) | 1,080 px | 2,160 px |
| 7.2 in / 18 cm (window) | 2,160 px | 4,320 px |
| 36 in / 90 cm (billboard) | 10,800 px | use vector |
Large-format printing is the exception that proves the rule: billboards are routinely output at 30-75 DPI because nobody stands close to one, and at that point the pixel count in the table above is meaningless. Send vector and let the RIP decide.
How small can a QR code be?
The practical floor for print is about 0.8 in / 2 cm on ordinary stock, whatever the 10:1 ratio says. Below that, ink spread merges adjacent modules on uncoated paper and the pattern stops resolving. On screen or on a gloss label with a short payload, codes down to 0.4 in / 1 cm can scan, but they have no margin left for angle, motion or poor light.
Three things buy back room at the bottom end, in order of how much they help: a shorter payload, error correction level Q or H, and a coated stock. A code encoding a seven-character short link at level H on gloss will beat a code encoding a 90-character campaign URL at level L on uncoated paper, at the same printed size, every time.
Why two codes the same size hold different amounts of data
A QR code is a grid, and the grid grows as the payload does, from 21×21 modules at version 1 to 177×177 at version 40. Keep the printed width fixed and add characters, and every module gets smaller. That is the whole mechanism, and it is why the length of what you encode is a print-quality decision rather than a technical footnote.
A Klip payload is 30 characters, which lands at version 3 with error correction M, a 29×29 grid. The same destination written out with campaign parameters is routinely 90 to 120 characters, which pushes you to version 6 or 7, a 41×41 or 45×45 grid. Same paper, so each module prints at roughly two-thirds the width, and two-thirds is the difference between a code that survives a print run and one that does not. The short link is not a branding flourish here.
If a code is already printed and failing, work through the troubleshooting guide.
Questions
The things people ask before they commit something to paper.
Can a QR code be too big?
Rarely, but yes. Phone cameras need the whole code inside the frame, so a code larger than about a third of the viewing area forces people to step back. On a billboard that is fine; on a table tent it means the code cannot be scanned from arm’s length.
Does the quiet zone count towards the size?
Yes. The quiet zone is the blank margin around the pattern, four modules wide, and scanners use it to find the code. Measure your printed code including that margin. Cropping it to save space is the most common cause of a code that will not scan.
Do I need a bigger code if it has a logo?
Add about 20%. A logo covers data modules, so the code has to be printed at error-correction level H and read more of the remaining pattern. More size gives the scanner more pixels per module, which is what buys back the reliability the logo costs.
What size QR code works on a business card?
The ratio gives 0.6 inches for a card read at six inches, but print it at 0.8 inches or 2 cm. That is the practical floor for consumer printing: below roughly 0.6 inches, ink spread on uncoated card starts merging modules and scan rates fall sharply.