Making a QR code takes a second. The problem is hearing “it will not scan” after it is printed on the cards.
It scanned on screen and fails on paper. The cause is almost always one of four things — all of them easy to lose to a layout decision.
1. Do not crop the quiet zone
The most common cause. A QR code is read on the assumption that there is white space around it — the spec asks for four modules’ worth. It is tempting to fit it flush into a frame, and doing so measurably lowers the scan rate.
2. Do not drop the error correction too far
QR codes carry recovery data so they survive damage. The levels are L (about 7%), M (15%), Q (25%) and H (30%) — how much can be missing and still be recovered.
For anything printed, displayed outdoors, or with a logo over the middle, Q or H is the safe choice. On screen, L is fine. Raising the level makes the code denser, so print it correspondingly larger.
3. Do not invert the colours
A light code on a dark background works on some readers and not others. Dark code, light background is the norm. If you must add colour, keep plenty of contrast — pale greys and colours close to the background are the ones to avoid.
4. Print it larger than feels necessary
As a rule of thumb, make one side about a tenth of the reading distance. Held in the hand on a business card, 1.5–2cm; on a poster read from a metre away, around 10cm. When unsure, go bigger — too small to scan is a worse problem than slightly ungainly.
Shorter URLs help. Fewer characters mean larger modules, which scan more easily at the same printed size. Strip long tracking parameters before generating if you can.
The shortened-URL and “dynamic QR” trap
Shorteners keep the code simple, and “dynamic QR” services let you change the destination later. Both are convenient, and both mean the destination now routes through that provider.
When you make one
This site’s QR code generator handles URLs plus email, phone, SMS, Wi-Fi and contact formats. Error correction and colours are under “more settings”. It exports both PNG and SVG — choose SVG for anything going to print, since it stays crisp at any size.
One last thing: scan the real thing before the print run. Reading on screen and reading on paper are different tests. A proof, scanned on a few different phones, is the check that actually catches problems.