You designed the perfect QR code. It links to the right page, the colors match your brand, and the call-to-action is compelling. But then you print it... and nobody can scan it.
The problem? Size.
Getting QR code dimensions right is one of the most overlooked steps in any QR code project. Too small and phones can't read it. Too large and you're wasting precious real estate. This guide gives you the exact sizes you need for every common use case — from tiny business cards to highway billboards.
The Golden Rule: The 10:1 Ratio
Before we get into specific sizes, memorize this one rule:
The maximum reliable scanning distance is roughly 10 times the width of your QR code.
So a QR code that's 3 cm (about 1.2 inches) wide can be reliably scanned from up to 30 cm (12 inches) away. A code that's 30 cm wide? Scannable from about 3 meters (10 feet).
This ratio accounts for modern smartphone cameras, but keep in mind that lighting, contrast, and data density all affect real-world performance. When in doubt, go slightly bigger.
Minimum QR Code Sizes by Use Case
Here are recommended minimum sizes based on typical scanning distances:
Business Cards (10–20 cm scanning distance)
- Minimum: 2 cm × 2 cm (0.8" × 0.8")
- Recommended: 2.5 cm × 2.5 cm (1" × 1")
- Tip: Use a vCard QR code so contacts save directly to the phone
Flyers and Brochures (15–30 cm)
- Minimum: 2.5 cm × 2.5 cm (1" × 1")
- Recommended: 3 cm × 3 cm (1.2" × 1.2")
Product Packaging (15–40 cm)
- Minimum: 2 cm × 2 cm
- Recommended: 3 cm × 3 cm
- Keep in mind curved surfaces — increase size by 20% on bottles and cylinders
Table Tents and Menus (30–60 cm)
- Minimum: 3 cm × 3 cm
- Recommended: 4 cm × 4 cm (1.6" × 1.6")
Posters (1–2 meters)
- Minimum: 10 cm × 10 cm (4" × 4")
- Recommended: 15 cm × 15 cm (6" × 6")
Banners and Trade Show Displays (2–5 meters)
- Minimum: 20 cm × 20 cm (8" × 8")
- Recommended: 30 cm × 30 cm (12" × 12")
Storefront Windows (1–3 meters)
- Minimum: 15 cm × 15 cm
- Recommended: 20 cm × 20 cm
Billboards and Large Signage (10+ meters)
- Minimum: 1 meter × 1 meter
- Recommended: 1.5 meters × 1.5 meters or larger
- Important: At these distances, use the simplest possible QR code with minimal data
QR Code Size for Digital Screens
QR codes on screens follow similar principles, but you measure in pixels instead of centimeters:
Smartphone screens (sharing via screen)
- Minimum: 150 × 150 px
- Recommended: 200 × 200 px
Computer monitors and tablets (30–60 cm)
- Minimum: 200 × 200 px
- Recommended: 250 × 250 px
TV and digital signage (1–5 meters)
- Minimum: 400 × 400 px
- Recommended: 500 × 500 px or larger
Presentation slides
- Minimum: 300 × 300 px
- Recommended: 400 × 400 px, placed in a corner with a clear call-to-action
When you create QR codes with QRDex, you can download them in SVG format, which scales perfectly to any size without losing quality — ideal when you need both print and digital versions from the same code.
5 Factors That Affect Scanability Beyond Size
Size matters, but it's not the only thing. Here's what else to watch:
1. Data Density
The more data your QR code encodes, the more modules (tiny squares) it contains, and the harder each one is to read at small sizes. A QR code linking to a short URL like qrdex.io/abc has far fewer modules than one encoding a full vCard with name, phone, email, and address.
Pro tip: Use dynamic QR codes instead of static ones. Dynamic codes always encode a short redirect URL regardless of where they point, keeping the code simple and scannable even at smaller sizes.
2. Quiet Zone
Every QR code needs a white border (called the "quiet zone") around it — at least 4 modules wide. Without it, scanners can't tell where the code ends and the background begins.
Never crop this border. If your design is tight on space, the quiet zone is non-negotiable.
3. Contrast
QR codes need strong contrast between the dark modules and the light background. Black on white is the classic choice for good reason. If you're using brand colors, test thoroughly — a dark blue on medium gray might look fine to your eyes but fail for phone cameras in mixed lighting.
4. Error Correction Level
QR codes have four error correction levels: L (7%), M (15%), Q (25%), and H (30%). Higher levels make the code more resilient to damage or partial obstruction, but they also add more modules.
If you're embedding a logo in the center of your QR code, use Level Q or H and increase the physical size by 15–20% to compensate for the added complexity.
5. Surface Material and Finish
Glossy surfaces can cause glare that makes scanning difficult. Textured or dark surfaces reduce contrast. If your QR code will be printed on a non-standard material (metal, fabric, glass), always test with multiple phones in the actual environment.
How to Test Your QR Code Size
Before committing to a print run, follow this quick testing checklist:
- Print a test copy at the exact size you plan to use
- Scan from the expected distance — not from 6 inches away while holding it in your hand
- Test with at least 3 different phones (iPhone, Android, older model)
- Test in realistic lighting — indoor fluorescent, outdoor sun, dim restaurant
- Try scanning at an angle — people rarely hold their phone perfectly straight
If you're using QRDex's scan analytics, you can track whether your codes are actually being scanned after deployment. If scan rates are low, size or placement might be the culprit.
Quick Reference Cheat Sheet
Scanning distance → Minimum QR code width:
- 10 cm → 1 cm
- 30 cm → 3 cm
- 1 meter → 10 cm
- 3 meters → 30 cm
- 10 meters → 1 meter
Remember:
- Use the 10:1 rule as your starting point
- Always include the quiet zone
- Dynamic QR codes stay small regardless of destination
- SVG format scales to any print size
- Test before you print in bulk
Create Perfectly Sized QR Codes with QRDex
QRDex makes it easy to generate QR codes in the right format for any use case. Download as SVG for infinite scalability, or export at a specific pixel size for digital use. With dynamic QR codes, your codes stay compact and scannable even at small sizes — and you can update the destination anytime without reprinting.
Need to generate codes at scale? The QRDex API lets you create and manage QR codes programmatically, with full control over size, format, and error correction.
Create your first QR code free →
Have questions about sizing for a specific project? Check out our Help Center or reach out — we're happy to help you get it right.