QR Code Size Guide: How Big Should Your QR Code Be?

The size of your QR code directly affects whether it can be scanned. Too small, and phones can't read it. Here's everything you need to know about QR code sizing for different applications.

The 10:1 Rule for QR Code Sizing

A simple rule: Divide the scanning distance by 10 to get the minimum QR code size.

• Scanning from 10 inches away → QR code should be at least 1 inch
• Scanning from 3 feet (36 inches) → At least 3.6 inches
• Scanning from 10 feet (120 inches) → At least 12 inches

This ratio ensures the phone camera can capture enough detail to decode the QR code accurately.

Minimum QR Code Sizes by Use Case

Factors That Affect Required Size

1. Data Density

More data = more modules (tiny squares) = needs to be bigger. A QR code with a simple URL has fewer modules than one containing a full vCard with name, phone, email, and address.

• Low density: Short URLs, phone numbers (can be smaller)
• High density: vCards, WiFi credentials, long text (need to be larger)

2. Error Correction Level

Higher error correction adds more data, making the code denser. If you're using high (H) or quartile (Q) error correction, increase the size by 20-30%.

3. Print Quality

Low-resolution printing can blur the edges of modules, making the code harder to scan. For low-quality printing (like newspapers or receipts), increase the size by 25%.

4. Surface Material

Glossy or reflective surfaces can cause glare. Textured surfaces may distort the code. Both situations require larger QR codes for reliable scanning.

The Quiet Zone Rule

Every QR code needs a quiet zone—a blank border around the code. This helps scanners identify where the code begins and ends.

• The quiet zone should be at least 4 modules wide on all sides
• As a rule of thumb: leave a white border equal to 10% of the QR code size
• Never let other graphics or text touch the QR code directly

Resolution Guidelines for Digital Use

For screens and digital displays:

• Mobile screens: Minimum 200×200 pixels
• Desktop/tablet: 300×300 pixels or larger
• Digital signage: Scale based on viewing distance (use 10:1 rule)
• Email: 150×150 pixels minimum (but 200×200 is safer)

Print Resolution: DPI Matters

For print, aim for at least 300 DPI (dots per inch). Here's what that means:

• 1-inch print = 300×300 pixel image at 300 DPI
• 2-inch print = 600×600 pixel image at 300 DPI
• For best results, use SVG format which scales infinitely without quality loss

Tips for Optimal QR Code Sizing

1. Test before printing—always scan your QR code at the expected distance
2. Use shorter URLs—URL shorteners reduce data density
3. Choose SVG for print—vector formats scale without pixelation
4. Add margin to your design—ensure the quiet zone isn't cut off
5. Consider the scanner—older phones may need larger codes
6. When in doubt, go bigger—it's better to have a code that's too big than one that won't scan

Common Size Mistakes to Avoid

• Putting too much data in a small code—simplify the content or increase size
• Forgetting the quiet zone—other design elements too close to the code
• Using low-resolution images—always export at appropriate resolution for intended use
• Not testing at actual distance—what works close up may fail from 10 feet away
• Placing on curved surfaces—distortion requires larger codes