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What a QR Code Actually Is, and How to Make One

October 22, 2026 · 4 min read

A QR code looks like static, but it's a grid encoding actual data — usually a URL, but also plain text, Wi-Fi credentials, or contact details. A phone camera decodes the grid pattern back into that data in a fraction of a second, which is why they took over from typing out a URL by hand.

Why they still scan when part of the code is damaged

QR codes are built with error-correction encoded directly into the grid, so a scanner can reconstruct the missing data even if up to roughly 30% of the code is scratched, covered, or printed poorly (at the highest error-correction level). That headroom is also why logos get placed in the center of a lot of branded QR codes without breaking the scan.

Making one

  1. Open the QR Code Generator.
  2. Choose what it should encode — a link, plain text, or a Wi-Fi network with its password.
  3. Download it as an image sized for print or screen display.

A detail worth checking before printing

A URL-based QR code only works if the link behind it keeps working — if the destination page moves or gets taken down after the code is already printed on packaging or a flyer, the code itself doesn't update. For anything printed at scale, pointing the code at a URL you control (rather than a one-off page you might restructure later) avoids having to reprint everything.

Reading one back

If you have a QR code as an image file rather than something to point a camera at — a screenshot, a scanned document — the QR code scanner decodes it directly from the uploaded image.