The distance rule
A reliable rule of thumb: the code's width should be at least 1/10 of the scanning distance. Dense codes need more.
| Where | Distance | Minimum size |
|---|---|---|
| Business card | 15–25 cm | 2 cm (0.8 in) |
| Flyer, menu, table tent | 30–50 cm | 3–5 cm (1.2–2 in) |
| Booth sign, poster | 1–2 m | 10–20 cm (4–8 in) |
| Window or banner | 3–5 m | 30–50 cm (12–20 in) |
Content changes density
A QR code is a grid of modules; more text means more, smaller modules at the same size. A vCard with name, mobile, email, company, title and website is about 150–250 characters — easy at 2 cm. Add a full address, a second phone, social links and a note, and it can triple. If the builder warns that your code is dense, trim it, print it bigger, or switch to Opens my card link.
Quiet zone, contrast, error correction
- Quiet zone: keep an empty margin of about 4 modules around the code (the standard asks for 4).
- Contrast: dark on light. Avoid light-on-dark, pastel-on-white and busy backgrounds behind the code.
- Error correction: level M (about 15% recovery) is a good balance for clean print; it's what this site uses. Codes with a logo in the middle need higher levels.
- Format: use SVG or PDF for print; a PNG should be at least 300 dpi at its printed size.
Test before a big print run
Print one copy at actual size, then scan it from the real distance with two different phones, in the light where it will hang.
Frequently asked questions
What is the minimum size for a QR code?
About 2 × 2 cm (0.8 in) for close-range use like business cards; larger for longer distances — roughly 1/10 of the scanning distance.
Why won't my printed QR code scan?
Usually it's too small for the amount of data, missing its white margin, low in contrast, or printed blurry. Print bigger, simplify the content or use SVG.
Does a QR code with more data need to be bigger?
Yes. More data means more modules; keep each module at least about 0.3–0.5 mm on a business card.
Is SVG or PNG better for printing?
SVG — it's vector and stays sharp at any size.
Contact files follow vCard 3.0 (RFC 2426); QR codes follow ISO/IEC 18004. Checked 2026-11-07.