CodeMaster AcademyWhat's actually encoded in a QR code
A QR code is just a grid-based way of storing text — the same URL, Wi-Fi credentials, or plain message you'd otherwise type out, packed into black-and-white squares a camera can read faster than a human can type. This tool takes whatever text or link you enter, runs it through the QR encoding algorithm client-side, and draws the resulting pattern straight to a canvas element for you to download.
Error correction, and why it matters
QR codes include built-in redundancy so they still scan even if part of the code is scratched, covered by a logo, or printed at low quality. That redundancy is called error correction, and it comes in four levels (L, M, Q, H) trading off storage capacity against damage tolerance. A code with high error correction can lose up to 30% of its data and still scan correctly — useful if you're planning to print it small or place a logo in the center.
Picking the right content type
Plain URLs and text are the simplest case, but QR codes can also encode Wi-Fi network credentials (so scanning connects a phone automatically), contact cards (vCard format), or pre-filled email and SMS drafts. If you're printing a code for public use — a menu, a flyer, a business card — test it with two or three different phone cameras before printing at scale, since older scanner apps handle some formats better than others.
Using this generator
Type or paste your content into the input field, adjust size if you need a specific pixel dimension for print, and the QR preview updates instantly. Download the result as a PNG once you're happy with it — the whole process runs in your browser, so nothing you type is sent to a server.
Common questions
Do QR codes expire?
No — a QR code generated this way encodes your content directly (a "static" code), so it works permanently and doesn't depend on any external service staying online.
Can I put a logo in the middle of my QR code?
Yes, as long as the code uses a high error-correction level; covering more than about 15-20% of the code's area risks scan failures even with maximum error correction.
Why did my printed QR code stop scanning?
Common culprits are printing too small, glossy paper causing glare, or excessive image compression blurring the fine grid pattern. Test a printed sample before ordering a large print run.
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Page last reviewed: July 2026