1. Payload
* Keep the URL short to minimise version and module density.
* Use HTTPS only.
* Link to a page that is live and tested before printing.
* Avoid session-based or expiring URLs in permanent print.
2. Symbol Design
* Error correction: M for clean environments, Q for outdoor, H if adding a logo.
* Module size: at least 0.5 mm on coated stock.
* Quiet zone: at least 4 modules on all sides.
* Contrast: dark modules on a light background, not the reverse, and at least 4:1 luminance ratio.
* Logo coverage: max 15% of symbol area at level H only.
3. Print and Materials
* Use vector SVG or 300 dpi PNG minimum.
* Match substrate to environment: coated stock indoors, weatherproof material outdoors.
* CMYK black: 100K, not rich black.
* Test a print proof before a full run.
4. Security
* Validate destinations before publishing.
* Use tamper-evident mounting in public locations.
* Monitor for sticker overlays and audit regularly.
5. Accessibility
* Print the destination URL in text near the code.
* Add alt text to digital QR images.
* Ensure the linked page meets WCAG 2.1 AA.
6. Measurement
* Use a separate short path per placement.
* Track visits, sessions, and conversions from each source.
* Document every code, its destination, and its placement.
Putting this into practice
Start with the smallest real test you can run. Generate the code, print it at the exact size you plan to use, and scan it with two different phones in the lighting where it will live. Check that the destination page loads quickly on a mobile connection and that the call to action next to the code tells people what they will get. If anything feels slow or unclear, fix it before you print a full batch, because reprints cost more than a short test. Keep a note of the size, material, and placement that worked so the next batch starts from a proven setup.
Common mistakes to avoid
The most common mistakes are easy to avoid once you know them. Long payloads make modules tiny, low contrast makes edges hard to read, and text placed too close to the border eats the quiet zone the scanner needs. Covering a corner finder pattern with a logo or a sticker breaks detection entirely, and a code placed behind glare or on a curved surface fails even when the print is perfect. Review each of these points on a proof copy, and treat any failure as a reason to adjust the design rather than a reason to blame the scanner.
Quick checklist
- Keep the payload as short as practical so modules stay large.
- Keep dark modules on a light background with strong contrast.
- Leave a clear quiet zone on all four sides of the symbol.
- Test the printed code at the real viewing distance and lighting.
- Confirm the destination page loads fast on a phone.
- Recheck the code after any change to the link, design, or placement.
Related tools and guides
- Use the [QR size calculator](/qr-size-calculator) to match the printed size to the expected scan distance before you commit to a print run.
- The [error correction simulator](/error-correction-simulator) shows how damage tolerance changes the density of the symbol at each level.
- Test every code with the [QR scanner](/qr-scanner) on more than one phone before you publish or print it.
- Create a fresh code with the [URL QR code generator](/url-qr-code-generator) when the destination is a web page.
- Run unfamiliar destinations through the [QR safety checker](/qr-safety-checker) before you share a code widely.
- The [blog](/blog) collects more guides on sizing, printing, security, and payments for QR codes.
