The Complete Guide to QR Codes

A QR code is a two-dimensional barcode that stores data in a grid of light and dark squares called modules. Unlike a traditional barcode, which holds data in one direction, a QR code packs information both horizontally and vertically — which is why it can store thousands of characters in a small square.

The three large squares in the corners are finder patterns. They let a camera locate the code and work out its orientation, so it scans whether it's upright, rotated, or slightly skewed. The rest of the grid encodes your content along with error-correction data that lets the code survive smudges, a printed logo, or a torn corner.

Although every QR code looks similar, the content inside can do very different things. A URL code opens a web page. A WiFi code joins a network. A vCard code saves a contact. There are also codes for email, SMS, phone calls, calendar events, geographic locations, payments (PayPal, PIX, crypto), and direct links into apps like WhatsApp, Telegram, and Messenger.

Choosing the right type matters because it controls what happens after the scan. A restaurant wants a URL code to a menu; a conference badge wants a vCard; a café wants a WiFi code on the table. Each type formats the data in a way phones recognise natively, so no special app is required.

A static QR code stores the content directly in the pattern. It is free, never expires, and needs no account — but it can never be changed once printed, and there is no way to know how many people scanned it.

A dynamic QR code stores a short link you control. When someone scans it, they reach a redirect service that records the scan and instantly forwards them to whatever destination you have set. You can edit that destination forever, and you get analytics: scans over time, devices, operating systems, browsers, and countries.

The rule of thumb: use static for permanent information like a WiFi password, and dynamic for anything you print at scale, might change, or want to measure. Getting this decision right before you print is the single biggest factor in whether a QR campaign succeeds.

Creating a QR code takes under a minute. Pick a type, enter your content, customise the design, and download. With a tool like QR Geni you can do all of this for free in the browser, and toggle a code to dynamic if you want it editable and trackable.

Export as PNG for screens and most print, or SVG when you need a vector that stays razor-sharp at any size — useful for large-format printing like posters and banners.

A branded QR code earns more scans because it looks trustworthy and intentional — but design choices can quietly break scannability. Keep strong contrast between the pattern and the background; dark modules on a light background is the safe default. If you invert or use gradients, make sure the pattern stays clearly darker than the background.

Respect the quiet zone, the empty margin around the code, so scanners can find it. If you add a logo, raise the error-correction level to High and keep the logo to roughly a quarter of the code's area. A call-to-action frame like "Scan me" measurably increases scans by telling people what to do.

Whatever you design, test the final code on two or three different phones before you print at scale. Thirty seconds of testing prevents an expensive reprint.

QR codes shine anywhere you want to connect something physical to something digital: restaurant menus, business cards, product packaging, event badges, retail shelf tags, real-estate signs, hotel rooms, gym equipment, and donation drives.

The common thread is removing friction. Instead of asking someone to type a URL, search a handle, or copy a wallet address, you let them scan and go. That reduction in effort is why QR codes convert offline attention into online action so well.

If a campaign matters, you want to know whether it worked. Dynamic codes record every scan with a timestamp, device type, operating system, browser, and approximate location. That lets you compare placements, spot peak times, and see which regions engage.

Because dynamic codes are editable, you can also run an experiment: point the same printed code at different destinations over time, or fix a broken link the moment you notice it, without reprinting anything.

The biggest mistake is printing a static code when you needed a dynamic one — discovering after the fact that you can't fix a typo or measure results. Others include making the code too small to scan from its intended distance, skipping the quiet zone, using low contrast, oversizing a logo, and never testing on real phones.

Avoid linking to a slow or non-mobile-friendly page, too: the scan is only half the journey. Send people somewhere fast and relevant, add a clear call to action, and your QR codes will do real work for you.