QR code size: how big to print it for the scanning distance
Work out how big to print a QR code from the scanning distance and the size of its squares, choose PNG or SVG, and test a proof before the full print run.
Make a printed QR code about one tenth as wide as the distance people scan it from: about 3 cm for a table card read from 30 cm, and about 15 cm for a poster read from 1.5 m. That’s a common rule of thumb, not a standard, and there’s no single minimum size. Readability depends on the size of the code’s small squares, and only a printed proof confirms a size.
This guide follows a made-up bakery that makes its code in Links and prints it on a table card, a flyer and a window poster. It doesn’t cover codes with colors or logos. To change where a printed code leads later, see the guide to changing a QR code’s destination.
Understand what makes a QR code readable
A QR code is a grid of small squares called modules. Version 1 is 21 modules on each side, and each higher version adds 4 per side. DENSO WAVE’s version page explains that the version depends on the amount of data, the type of characters and the error correction level.
Every code also needs a clear margin, the quiet zone, four modules wide on all sides, as DENSO WAVE’s code-area page explains. So the printed width includes 8 extra modules.
At the same printed width, more modules means smaller modules. DENSO WAVE’s module-size page says larger modules read more reliably and each scanner has its own limit, so print as large as the space allows. To find a code’s module size, divide its printed width by the number of modules across it, border included.
Keep the encoded address short
A longer encoded address needs more modules. The bakery compared two addresses, each printed 3 cm wide with its border, at the error correction level Links uses:
| Encoded address | Grid | With border | Module size |
|---|---|---|---|
| Short link, 31 characters | 29 × 29 | 37 × 37 | about 0.8 mm |
| Address with UTM tags, 151 characters | 49 × 49 | 57 × 57 | about 0.5 mm |
The short link’s modules are about one and a half times as wide. To match them, the tagged address would need a code about 4.6 cm wide.
Every Links QR code holds a reunified.link short address with 8 characters after the domain, so it’s always 37 modules wide with its border. Put tracking tags in the link’s stored destination, not in the code; the UTM guide shows how.
Estimate the size from the scanning distance
Start with the one-tenth rule, then go larger for poor light or scanning at an angle, and prefer a flat, matte surface. The bakery’s starting widths, border included:
| Placement | Distance | Width | Module size |
|---|---|---|---|
| Table card | about 30 cm | 3 cm | about 0.8 mm |
| Flyer in the hand | 20 to 30 cm | 3 cm | about 0.8 mm |
| Window poster | about 1.5 m | 15 cm | about 4 mm |
Try these in a proof; none is guaranteed to scan.
Choose PNG or SVG for your layout
In Links, open a link, press QR code, then choose Download PNG or Download SVG. Both are dark on white and include the white border.
The PNG is 592 × 592 pixels, about 5 cm wide at 300 dpi: enough for the table card and the flyer. The SVG stays sharp at any size, so use it for the poster, and whenever your design tool accepts it. Set the final width in the layout.
Whichever file you use:
- Scale width and height together; never stretch the square.
- Keep the white border clear of text, frames and logos.
Print a proof and test it like a visitor
Print the code at its final size on the real material. A plain office print won’t show the glare of a glossy finish. Then test it:
- Scan with at least three phones, including an older one.
- Stand at the real distance, in the real light. The bakery scans the poster through the window, by day and in the evening.
- Try a slight angle as well as straight on.
- Check that the right page opens.
- Write down the phone, distance, light and result.
Order the full run only when every phone passes.
When the code still won’t scan
Check these causes in order, changing one thing at a time:
- Too small for the distance: print it larger, encode a shorter address, or place it closer to where people stand.
- Border cropped: restore the full white margin from the downloaded file.
- Low contrast or glare: use a matte finish and a plain light background.
- Curved surface: move the code to a flat area.
If the code scans but the wrong page opens, the print isn’t the problem; see the troubleshooting guide. Do QR codes expire? explains why printed codes stop working, and the business card guide covers small cards.
Creating links and their QR codes is free in the Links app, and each counted click, scans included, costs 0.05 credits. Links keeps the encoded address short; your printed proof confirms the size.