Get your QR code size right the first time. This guide covers minimum sizes, the scanning distance formula, and recommended sizes for common use cases.

The 10:1 rule

The most important guideline for QR code sizing:

Scanning distance ÷ 10 = Minimum QR code width

If someone will scan your QR code from 1 meter away, the code needs to be at least 10 cm wide. From 3 meters, at least 30 cm.

This rule ensures the camera can resolve individual modules (the small squares that make up the code).

Minimum sizes

These are absolute minimums. When in doubt, go larger.

Recommended sizes by use case

Print resolution

For print materials, use 300 DPI as your standard.

FreeQR exports QR codes at up to 1920 × 1920 pixels, which is sufficient for: - All small print items at 300 DPI (up to ~16 cm) - Banners at 150 DPI (up to ~32 cm)

Quiet zone

The quiet zone is the blank space around your QR code. It helps scanners detect where the code begins and ends.

Minimum quiet zone: 4 modules (the width of 4 small squares in the code)

Never crop this space or place text and graphics too close to the code edges. In FreeQR, the Frame section lets you adjust the margin percentage.

What affects scannability at small sizes

Data amount

More data means more modules, which means a denser pattern. Dense patterns need larger physical sizes to remain scannable.

Keep your encoded content short. Use URL shorteners when linking to long addresses.

Error correction level

Higher error correction adds redundant data, increasing code density. Use the lowest level appropriate for your environment:

Surface material

Matte surfaces scan reliably. Paper, cardboard, and non-glossy vinyl work well.

Glossy surfaces create reflections that interfere with scanning. If you must use glossy materials, increase your QR code size by 20–30% and test thoroughly.

Curved surfaces

QR codes on bottles, cans, or curved packaging need extra care. Place the code on the flattest area possible and keep it small relative to the curve diameter.

Lighting

Bright direct light causes glare. Dim environments make it harder for cameras to capture detail. Test your codes in the actual lighting conditions where they will be used.

How to calculate your size

1. Estimate scanning distance — How far will people be when they scan?
2. Apply the 10:1 rule — Divide distance by 10
3. Compare to minimum — Use at least 2 cm for close-range items
4. Add margin for safety — Round up, especially for challenging environments
5. Include quiet zone — Add blank space around all sides

Example: A poster in a hallway scanned from 1.5 meters

• 150 cm ÷ 10 = 15 cm minimum
• Recommended: 15–20 cm to account for varying distances

Common mistakes

Too small on business cards

A 1 cm QR code looks tidy but often fails to scan. Use at least 2.5 cm.

Stretching low-resolution images

Enlarging a small PNG creates blurry, unscannable codes. Always export at the maximum resolution available.

Cropping the quiet zone

Trimming white space to fit your design breaks scannability. Always preserve the margin.

Low contrast

Light gray on white or subtle color combinations may look elegant but scan poorly. Stick to dark on light with strong contrast.

Testing before printing

Always test your QR code before mass printing:

1. Print at the exact final size
2. Scan from the expected distance
3. Test on both iPhone and Android
4. Try in different lighting conditions
5. Verify on the actual material (paper type, finish)

A few minutes of testing prevents wasted print runs.

Quick reference

• 10:1 rule: Size = scanning distance ÷ 10
• Absolute minimum: 2 × 2 cm
• Print resolution: 300 DPI
• Quiet zone: 4 modules minimum
• When uncertain: Go larger

Related articles

• How to customize your QR code design
• How to export your QR code
• QR code color guidelines