See how a QR code fits the space you have. Enter the width and what the code will contain to get the exact printed size, the blank margin it needs, and whether your print resolution is high enough. Scanning distance can’t be calculated reliably, so the page explains what affects it instead.
Printed size, margin included
3 cm × 3 cm
1.181 in × 1.181 in. The code itself is 2.3 cm (0.89 in) with a 3.6 mm blank margin on every side.
Meets print-resolution guidance at 300 dpi
Each square is 10.7 printer dots wide. DENSO WAVE, which invented the QR code, recommends at least 4.
This checks that a printer can draw every square cleanly. It doesn’t guarantee that phones will scan the code: distance, camera, light and contrast matter too.
How far away will it scan?
No reliable formula can tell you. Larger squares can be read from farther away, and every phone needs some distance to focus. Print a proof at 100% and scan it from the real distance, in the real light, with more than one phone. Why there’s no distance number
For a raster file, export at least 355 × 355 px. A vector file (SVG or PDF) avoids the question.
A QR code is a square grid of modules, the small black and white squares. Its printed size is the number of modules across multiplied by the size of one module, so everything the calculator shows follows exactly from the space you have and what the code contains.
modules = 17 + 4 × version
Every standard QR code is one of 40 versions, from 21 × 21 modules (version 1) to 177 × 177 (version 40). More content or a higher error-correction level means a higher version. The calculator encodes your content to find the real count.
width in modules = modules + 2 × 4
The QR code specification requires a blank margin 4 modules wide on every side. It is part of the space the code needs, so the calculator always includes it.
module = printed width ÷ width in modules
Divide the width you have, margin included, by the modules across. That gives the size of each square exactly.
dots = module × dpi ÷ 25.4 (aim for 4+)
DENSO WAVE recommends at least 4 printer dots per module so every square prints cleanly. That is print guidance, not a promise that phones will scan the code.
A QR Rapid dynamic code holds a short link, which encodes to 25 × 25 modules at error-correction level M. With the margin that is 33 modules across. Given 4 cm of space, each square is 40 mm ÷ 33 = 1.21 mm, the code itself is 3 cm (1.19 in) and the margin is 4.8 mm on every side. At 300 dpi each square is 14.3 printer dots wide, comfortably above the recommended 4.
Most printed codes that fail do so because of the artwork around them or the print process, not the code itself.
Leave 4 modules of blank space on every side. Text, borders, photos and the edge of the page all count as intrusions. A frame or call to action can sit outside it.
DENSO WAVE, which invented the QR code, recommends that each module is at least 4 printer dots wide. Tiny modules on a low-resolution printer blur or vary in width.
SVG or PDF artwork stays sharp at any size. If you must use a PNG or JPEG, make it large enough for the print resolution: the calculator gives the pixel width.
Dark modules on a light background are the safest choice. Colours, gradients and logos can work, but they use up some of the code’s margin for error, so test them.
Designing packaging or a campaign? The QR codes for design page covers exporting QR Rapid codes as SVG for layout work.
Exact printed widths, margin included, for the same square size with two kinds of content at error-correction level M. The table compares density only: it does not say which distance each size suits.
| Module size | Dynamic code (25 × 25) | Long URL, static (45 × 45) | Dots at 300 dpi |
|---|---|---|---|
| 0.5 mm (0.02 in) | 1.7 cm (0.65 in) | 2.7 cm (1.04 in) | 5.9 |
| 0.8 mm (0.031 in) | 2.6 cm (1.04 in) | 4.2 cm (1.67 in) | 9.4 |
| 1.2 mm (0.047 in) | 4 cm (1.56 in) | 6.4 cm (2.5 in) | 14.1 |
| 2 mm (0.079 in) | 6.6 cm (2.6 in) | 10.6 cm (4.17 in) | 23.6 |
| 4 mm (0.157 in) | 13.2 cm (5.2 in) | 21.2 cm (8.35 in) | 47.2 |
The long URL is https://www.example.com/products/summer-collection-2026?utm_source=flyer&utm_medium=print&utm_campaign=summer. Encoded directly in a static code, it needs far more modules than a dynamic code, which holds a short QR Rapid link and can be pointed somewhere else after printing. The same geometry applies to vCard codes on business cards and menu codes on table signs.
The printed size can be calculated exactly. The distance a phone can scan it from cannot: two phones looking at the same print can behave very differently.
You will often see a 10:1 rule (a code about one tenth as wide as the scanning distance), or a version based on module size taken from a sizing table QRStuff published in 2011 for 3–4 megapixel cameras. Neither is a standard, neither has been validated against today’s phones, and the 10:1 rule ignores how much the code contains. QR Rapid has not run its own distance tests, so this calculator does not turn a distance into a size.
What does hold is the direction: larger squares can be read from farther away, and strong contrast, good light and a flat, matte surface all help. For comparison, GS1 sets a minimum module of 0.396 mm for codes scanned at retail checkouts, which is a scanner requirement rather than a phone guarantee.
There is no single correct size, and no validated formula that turns a scanning distance into a size. Start from the space you have. The printed width, including the blank margin, divided by the number of modules plus 8 gives the size of each square: a QR Rapid dynamic code printed 4 cm (1.57 in) wide has squares of about 1.21 mm. Check that each square is at least 4 printer dots wide, then scan a printed proof from the real distance. Larger squares are easier to read from farther away.
There is no universal minimum for phone scanning. DENSO WAVE, the inventor of the QR code, says the smallest readable module depends on the scanner and the printer. GS1 sets a minimum module size of 0.396 mm for QR codes scanned at retail point of sale, which is 1.5 cm across for a 29-module code with its quiet zone. That is a retail scanner figure, not a guarantee for every phone.
The quiet zone is the blank margin around the code. The QR code specification requires it to be four modules wide on every side, so it adds eight modules to the width and height. Reserve that space in your layout and keep text, images and edges out of it.
It can. Higher error-correction levels (L, M, Q, H) store more recovery data, so the same content may need more modules, and at the same printed width each module is then smaller. QR Rapid generates codes at level M.
A dynamic code holds a short QR Rapid link rather than your full address, so it needs fewer modules. At level M, a QR Rapid short link encodes to 25 × 25 modules, while the long campaign URL used in the table on this page needs 45 × 45. Fewer modules means each one can be larger in the same space.
It depends on the size of each square and on the phone, its camera and focus, the light, the angle, the contrast and the print quality. There is no validated number that covers all of these. Larger squares can be read from farther away, and every phone also has a minimum focusing distance, so a small code held too close may not scan either. Test a printed proof at the distance people will really use.
You will often see the rule that a code should be about one tenth as wide as the scanning distance, or a version based on module size taken from a 2011 sizing table that assumed 3–4 megapixel cameras. Neither is a standard or has been validated against today’s phones, and the 10:1 rule ignores how much the code contains. This calculator does not use them. Use a printed test instead.
Use a vector format (SVG or PDF) for print artwork whenever you can, because it stays sharp at any size. If you need a raster image, the pixel width is the printed width in inches multiplied by the print resolution. DENSO WAVE recommends that each module is made up of at least four printer dots.
Print a proof at 100% scale and measure it, margin included. Scan it from the real distance with more than one phone, ideally an iPhone and an Android phone, in the light and at the angle people will use. If it will not scan very close up, step back: the camera may be too close to focus. If it will not scan from farther away, print it larger or reduce what it contains.
The geometry follows the QR code specification as published by DENSO WAVE and GS1. The QRStuff table is listed because the FAQ describes the rule of thumb it led to; the calculator does not use it.
A dynamic QR Rapid code holds a short link, so it stays compact on print, and you can change where it goes and track scans after it is printed.