1. What Is Print Growth
Ink spreads on paper fibers. Dark modules grow, and light gaps shrink. If growth is large, isolated light modules fill in and adjacent dark modules merge. Use our [QR size calculator](/qr-size-calculator) to plan adequate module sizes that tolerate expected dot gain.
2. Where It Is Worst
Uncoated paper, newsprint, and corrugated board spread ink most. Coated and synthetic stocks spread the least. Test on actual substrates using our [printed QR tester](/printed-qr-tester) before production runs.
3. Compensation
* Use larger modules on absorbent stock.
* Ask the printer for a slightly reduced dark module size (a few percent) if their proofing shows growth.
* Avoid very high version numbers on rough substrates—keep payloads short with our [URL generator](/url-qr-code-generator).
4. Verify
Print a proof on the real stock and test on older phones in typical lighting with a [QR scanner](/qr-scanner). Formal grading under ISO/IEC 15415 reports a print growth measurement. Follow our [QR placement guide](/qr-placement-guide) to ensure adequate quiet zones that don't get consumed by dot gain. Use our [error correction simulator](/error-correction-simulator) to understand how print quality affects error recovery.
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.
