A QR code is a two-dimensional barcode that stores text. Point a phone camera at it and the phone reads out whatever was encoded, usually a URL. It exists to bridge the physical and the digital: a poster, a business card, a menu, a piece of hardware, a slide at the back of a room.

The reason to generate one locally rather than through a typical online service is worth being explicit about. Many free QR generators encode a link to their own domain that redirects to your destination, so they can count scans. That gives them analytics and gives you a code that breaks permanently if their service disappears or starts charging. The codes here encode your content directly, with no intermediary and no dependency on this site continuing to exist.

Beyond plain links, a few conventions let a QR code do more than open a page. A specially formatted WiFi string joins a network without typing the password, which is why cafes put them on the wall. A vCard block adds a contact. A mailto or tel URI starts an email or a call. The tool has presets for these so you do not have to remember the exact syntax.

Error correction is the setting most worth understanding. QR codes include redundant data so they still scan when part of the code is dirty, creased, or covered by a logo. Higher correction survives more damage but packs the data into more, smaller modules, which makes the code harder to read at a distance or at small print sizes. Medium is a good default; go higher only if the code will be printed somewhere it may get damaged.

You can also style the code: rounded, fluid, dot or diamond modules, reshaped and recoloured corner patterns, ready-made presets, and your own logo in the middle. Each of those costs some reliability, so the tool checks the result as you go. Its limits come from testing a real decoder rather than from the usual advice: at level H the largest centred logo that still scanned covered about 14 percent of the code, not the 30 percent the published recovery figure implies.

You can download as PNG for the web or as SVG for print. SVG is the right choice for anything that will be scaled, since it stays sharp at any size.