Wrong sizing is a top reason printed QR codes fail. There's really one principle: the farther away people scan, the bigger the code must be.
The formula
Minimum QR size = scanning distance ÷ 10
Recommended sizes by use
- Business card — 2×2 cm (scanned from 10–20 cm)
- Menu / table tent — 3×3 to 4×4 cm
- A4 poster — 5×5 cm or larger
- Storefront sign — 10×10 cm or larger (scanned from ~1 m)
- Roadside sign / billboard — work from real distance: scanned from 5 m, the code needs to be at least 50 cm wide
Which file to print from
For print, use SVG — it scales infinitely without pixelation. If your print shop needs a raster file, export a 2048×2048 PNG from the QR generator (choose the size under "More options").
Don't forget the quiet zone
Leave empty space around the code at least 4 modules wide, keep other graphics away from it, and always test-scan from the real usage distance before ordering a large print run.