What Is a QR Code?
A QR code (Quick Response code) is a square grid of black and white modules that stores information a phone camera can read instantly. Unlike the old 1D barcodes on shop items, a QR code holds far more data and works in any orientation.
How does a QR code work?
The pattern encodes data in a machine-readable matrix. Three large squares in the corners help the scanner locate and orient the code, while smaller alignment patterns keep it readable even when printed on a curved surface. Built-in error correction means a code can still scan even if it is partly dirty, folded, or obscured.
Common types of QR codes
- URL QR code — opens a website when scanned. The most popular use.
- Text QR code — shows a message directly on screen, no browser needed.
- Wi-Fi QR code — connects a device to a network without typing the password. See our Wi-Fi QR code guide.
- vCard QR code — saves a contact to the phone's address book. See our vCard QR guide.
Static vs dynamic QR codes
A static code embeds the data directly and cannot be changed after printing — perfect for free, permanent use. A dynamic code stores a short link that can later point somewhere new and track scans, but it depends on a paid service. For most people, a free static code is all they need.
Ready to make one? Use our free QR code generator — paste a link or text, scan or download the SVG, no sign-up required.
Frequently Asked Questions
What does QR stand for?
QR stands for 'Quick Response'. The format was created in 1994 so factory parts could be scanned at high speed; today it is the most common 2D barcode in the world.
Are QR codes free to generate?
Yes. Generating a static QR code is free and requires no account. Paid services only add extras like editable (dynamic) codes, scans analytics, and branded design.
Do QR codes expire?
A static QR code never expires and is not tied to any server. A dynamic QR code can expire or stop working if its paid hosting plan lapses, because the code points to a redirect URL.
Can a QR code contain plain text?
Yes. Beyond links, a QR code can store text, Wi-Fi credentials, contact details (vCard), email, SMS, and more. Anything you can type can be encoded.
Is it safe to scan QR codes?
Scanning is safe, but a code can open any website. On phones, preview the link before tapping through, and never enter sensitive credentials on unfamiliar pages opened from a scan.