The Standard Business Card Canvas
A standard ISO 7810 ID-1 business card measures 85.6×54mm (3.370×2.125 inches). This modest canvas must accommodate your name, title, company, contact details, and increasingly a QR code. Getting the QR code sizing right on a business card is both a spatial geometry problem and an optical engineering challenge.
The 10:1 Distance-to-Size Rule Applied
A business card is typically scanned from a distance of 20–30 cm — the natural distance at which a person holds a card while looking at it and simultaneously pointing their phone camera. Applying the standard 10:1 optical ratio:
Minimum QR Width = Scanning Distance ÷ 10 = 25cm ÷ 10 = 2.5cm = 25mm
However, for business cards we can apply the aggressive 8:1 ratio (used for well-controlled lighting conditions and modern flagship cameras):
Conservative Minimum = 25cm ÷ 8 = 31mm
In practice, a 20mm QR code works reliably on business cards because modern flagship smartphone cameras (iPhone 16, Pixel 9, Samsung S24) can decode high-quality printed QR codes at 20mm from 25cm in adequate indoor lighting. However, for maximum compatibility across budget Android devices and older iPhones, 25–30mm is the recommended target size.
Optimal Business Card QR Layout
The QR code typically occupies the bottom-right corner of a standard business card. A 25×25mm QR code with a 3mm quiet zone on all sides requires 31×31mm of total reserved space — approximately 36% of the card's width. This typically works well with a two-column layout where contact text occupies the left 55mm and the QR code occupies the right 31mm.
Payload and Version Implications
For a business card QR code, keep the payload minimal:
- Preferred: A short URL to your LinkedIn profile or personal website (25–50 characters) → Version 2 at Level M (25×25mm print)
- Acceptable: Full vCard 3.0 with name, phone, email, URL (150–250 characters) → Version 6 at Level M (requires 30mm print size)
- Avoid: Full vCard with photo, multiple addresses, extended bio (500+ chars) → forces Version 15+ which at 25mm creates modules too small for reliable scanning
Print Specifications
Business cards are typically printed by offset lithography at 1200–2400 DPI or by digital laser/inkjet printing at 600–1200 DPI. At 20mm QR code size:
- Module width = 20mm ÷ (modules across for the version)
- For Version 2 (25 modules): module width = 0.80mm — well above the 0.35mm minimum
- For Version 6 (41 modules): module width = 0.49mm — at the threshold; use Level M not Level H
Always send QR codes to the print shop as vector SVG or lossless PDF. Never send a 72 DPI JPEG — the lossy compression creates ringing artifacts at module boundaries.