QR Code Generator

What Is a QR Code?

QR stands for Quick Response. A QR code is a two-dimensional barcode that can be scanned by any smartphone camera to instantly open a website, display information, save a contact, connect to Wi-Fi, initiate a payment, or trigger any action the encoded data supports. QR codes were invented in 1994 by Denso Wave, a Toyota subsidiary, originally for tracking automotive parts. They entered widespread consumer use gradually, but the COVID-19 pandemic — which prompted restaurants, venues, and health authorities worldwide to adopt contactless information sharing — triggered a massive acceleration in QR code adoption that has continued ever since.

Today, QR codes appear on restaurant menus, product packaging, business cards, posters, museum exhibits, payment terminals, public transport tickets, and more. The ability for any smartphone to scan a code and take immediate action has made QR codes one of the most versatile and practically useful information technologies of the past decade.

How QR Codes Work

A QR code stores data as a pattern of black and white squares arranged in a grid. The code includes the data itself, error correction information, alignment patterns (that allow scanning at any angle), timing patterns, and format information. The scanning device's camera captures the pattern and software decodes it back into the original string.

QR codes can store different types of data: URLs (the most common), plain text, contact information (vCard format), calendar events (iCal format), Wi-Fi network credentials (SSID and password), geographic coordinates, SMS or email drafts, and phone numbers. The type of content is often determined by a prefix — a URL starts with http:// or https://, a phone number with tel:, Wi-Fi credentials with WIFI:. Most smartphone QR scanners detect the content type automatically and offer the appropriate action.

Error Correction Levels Explained

QR codes have a built-in error correction mechanism that allows them to be read even if part of the code is damaged, dirty, or covered. There are four error correction levels: Low (L) allows up to 7% of the code to be damaged — this produces the smallest, simplest code and is appropriate for clean digital displays. Medium (M) allows up to 15% damage — the recommended choice for most uses, balancing size and reliability. Quartile (Q) allows up to 25% damage — useful when codes will be used in environments with potential soiling or partial obstruction. High (H) allows up to 30% damage — the largest code but the most resilient, ideal for printed materials and outdoor use. Higher error correction also allows designers to overlay a logo in the centre of a QR code — as long as the logo covers less than the error correction capacity, the code will still scan.

Best Practices for QR Code Design and Use

Always test your QR code after generating it — scan it with your own phone before printing or publishing. Print at sufficient size — for most scanning distances, a 2cm × 2cm minimum is recommended; larger for codes that will be scanned from a distance. Use high contrast — black on white is most reliable. Coloured QR codes can work but reduce scan reliability, especially with lighter colours. Ensure quiet zone — there should be a white border of at least 4 modules (the small squares) around the entire code; codes that extend to the edge of a print element often fail to scan. Keep URLs short — longer content creates denser, harder-to-scan codes; URL shorteners can help. And always include the destination URL visually near the QR code so users know what they are scanning before they do so.

Frequently Asked Questions

Do QR codes expire?

A static QR code — the kind this tool generates, which encodes the URL directly — never expires. As long as the URL it points to remains accessible, the code will continue to work indefinitely. Dynamic QR codes (offered by some paid services) redirect through a URL shortener that can be changed later, which allows the destination to be updated without regenerating the code — but these require an ongoing subscription to the service managing the redirect.

How much text can a QR code hold?

The maximum capacity depends on the data type and error correction level. For alphanumeric content, a maximum-size QR code can hold up to 4,296 characters. For URLs, this is more than sufficient. Keep in mind that longer content creates denser codes that are harder to scan — for best results, keep encoded text under 200 characters where possible.

Can I put a logo in the centre of my QR code?

Yes, but carefully. The logo must cover less area than the code's error correction capacity allows. With High (H) error correction selected, you can safely cover up to about 30% of the code area with a logo without preventing scanning. Always test after placing a logo, as even small misalignments can push the covered area over the functional threshold.

Which download format should I choose — PNG or SVG?

SVG (Scalable Vector Graphics) is ideal for professional design work — it can be scaled to any size without losing quality, making it perfect for print materials from business cards to billboards. PNG is a raster format — it has a fixed pixel resolution — but is more universally compatible for web, presentation, and document use. This tool generates high-resolution PNGs (4x scale) suitable for most printing needs. If you need the code at a very large print size, use SVG.

Are QR codes accessible?

Standard QR codes are not accessible to users with visual impairments who use screen readers, since they are purely visual. When using QR codes in accessible contexts, always include a text alternative — either print the URL near the code or provide a companion link. For digital contexts (web pages, PDFs), include an alt text description on the QR code image and provide the URL as a standard hyperlink alongside it.

QR Code Applications by Industry

Restaurants and hospitality: digital menus, table ordering, payment, and review links. Retail and e-commerce: product information, assembly instructions, re-ordering links, and loyalty programmes. Marketing and advertising: bridging print advertising to digital content, tracking campaign effectiveness. Healthcare: patient wristbands, medication information, appointment check-in. Events: ticketing, check-in, programme guides, and networking. Education: supplementary resources, interactive worksheets, library catalogues. Real estate: property listing links on for-sale signs, virtual tour access. Logistics and manufacturing: asset tracking, inventory management, part identification — the original use case for which QR codes were invented.