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Explainer1 min readUpdated July 8, 2026

What is a QR code (and how to make one)?

Short answer

A QR code is a two-dimensional barcode that a phone camera can scan to open a URL or read text. You generate one by entering the link or text; the tool encodes it into the pattern of squares.

How a QR code works

QR stands for Quick Response. The pattern of black and white squares encodes data — most often a URL — plus error correction that lets it still scan when partly damaged or obscured. A phone camera decodes it instantly.

What a QR code can hold

  • A website URL — by far the most common use
  • Plain text or contact details (vCard)
  • Wi-Fi network name and password
  • An email address or phone number to prefill
Try it: QR Code GeneratorTurn a link or text into a downloadable QR code, generated locally.Open tool
Shorter data scans more reliablyMore data means a denser code that is harder to scan at small sizes or distances. Keep URLs short and clean — strip tracking parameters first with a URL cleaner.

Make one that scans

  • Keep strong contrast: dark code on a light background
  • Leave a quiet margin (blank space) around the code
  • Print or display it large enough for the scan distance
  • Test it with a real phone before publishing or printing

References

Questions

Do QR codes expire?

A static QR code encodes the data directly and never expires — it always points to what you encoded. Only dynamic QR codes from third-party services, which redirect through their servers, can stop working if that service ends.

Can a QR code contain more than a link?

Yes. QR codes can hold plain text, contact cards, Wi-Fi credentials, email addresses, and phone numbers, though URLs are the most common because they are short and universally useful.

Is the QR code generated privately?

Yes. The code is created inside your browser tab from the text you enter. Nothing is uploaded or stored.

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