The 10:1 Distance-to-Size Rule
The most reliable rule of thumb for QR code sizing is the 10:1 ratio: divide the expected scan distance by 10 to get the minimum QR code width.
- A business card scanned from 15 cm → minimum code size 1.5 cm
- A table tent scanned from 30 cm → minimum code size 3 cm
- A poster scanned from 2 m → minimum code size 20 cm
- A billboard scanned from 20 m → minimum code size 2 m
Key Insight
Size by Application
Recommended QR code sizes by application
| Application | Typical Distance | Minimum Size | Recommended Size |
|---|---|---|---|
| Business card | 10–15 cm | 1.5 cm | 2 cm (0.8 in) |
| Product label | 15–30 cm | 1.5 cm | 2.5 cm (1 in) |
| Restaurant table tent | 20–40 cm | 2 cm | 3 cm (1.2 in) |
| Flyer / A4 handout | 20–30 cm | 2 cm | 3 cm (1.2 in) |
| Poster (A2/A1) | 1–3 m | 10 cm | 15 cm (6 in) |
| Banner / roll-up | 1–5 m | 15 cm | 25 cm (10 in) |
| Billboard | 10–30 m | 1 m | 2 m (6.5 ft) |
| Digital screen | 30–100 cm | 3 cm | 5 cm (2 in) |
Module Count and Data Density
A QR code's version determines its module grid size. Version 1 is 21 × 21 modules; each step adds 4 modules per side, up to Version 40 at 177 × 177. More data means a higher version, more modules, and a larger minimum print size.
How data length affects minimum print size
| Data Length | Typical Version | Modules | Min Size at 300 DPI |
|---|---|---|---|
| Short URL (< 30 chars) | 2 (25 × 25) | 625 | 2.1 cm (0.8 in) |
| Medium URL (30–60 chars) | 4 (33 × 33) | 1,089 | 2.8 cm (1.1 in) |
| vCard (150 chars) | 7 (45 × 45) | 2,025 | 3.8 cm (1.5 in) |
| Long text (300 chars) | 12 (65 × 65) | 4,225 | 5.5 cm (2.2 in) |
Shorten Your Data
DPI and Print Resolution
DPI (dots per inch) determines how sharp the printed modules appear. Each module must contain enough printed dots to be clearly distinguishable from its neighbours.
DPI guidelines for QR code printing
| DPI | Quality | Use Case |
|---|---|---|
| 72 | Screen only | Web graphics, email signatures |
| 150 | Acceptable | Large-format signage, banners |
| 300 | Standard | Business cards, flyers, packaging |
| 600+ | Premium | High-end packaging, security printing |
Calculating Pixel Dimensions
To find the required pixel width for a given print size and DPI:
Pixels = Print width (inches) × DPI
A 2.5 cm (≈ 1 inch) QR code at 300 DPI needs a 300 × 300 px source image. Our generator exports up to 4096 px, which covers all commercial print scenarios.
Quiet Zone Requirements
The quiet zone is the blank margin around the QR code. ISO 18004 specifies a minimum of 4 modules on each side. This margin helps scanners distinguish the code from surrounding graphics.
Do Not Crop the Quiet Zone
Error Correction and Size Trade-offs
Higher error correction levels add redundancy data, increasing the module count and therefore the minimum print size. But they allow the code to remain scannable even with damage or a logo overlay.
Error correction level trade-offs
| EC Level | Data Recoverable | Size Increase | Logo Overlay |
|---|---|---|---|
| L (Low) | ~7% | Baseline | Not recommended |
| M (Medium) | ~15% | +10% | Small logos |
| Q (Quartile) | ~25% | +25% | Medium logos |
| H (High) | ~30% | +40% | Large logos |
Did You Know?
Testing Your Print Size
Before committing to a full print run:
- Export the QR code at target DPI and dimensions.
- Print a single test copy on the actual material (paper, vinyl, metal).
- Scan from the expected distance with at least two different phones.
- Scan under the expected lighting conditions (indoor, outdoor, low-light).
If the code fails to scan on the first attempt, increase the size by 20% and retest.
Calculate your exact QR size
Enter your scan distance and data type to get precise dimensions.