About QR Codes
A QR code (Quick Response code) is a two-dimensional barcode that can hold short text, URLs, contact cards, Wi-Fi credentials, or payment details. Almost every modern smartphone camera recognises one automatically, so they have become a reliable bridge between a printed poster or physical object and a digital action — opening a page, adding a contact, connecting to a network.
This generator takes any text or URL and produces a downloadable PNG you can print, paste into a slide deck, or embed on a page. The whole thing runs in your browser, so even codes that encode private URLs (internal dashboards, tokenised one-time links) never leave your machine.
QR codes are tolerant of damage thanks to built-in error correction: even if up to roughly 30% of the image is scratched, dirty, or covered with a logo, most scanners still read it correctly. That is why you can often see QR codes with a brand mark in the middle — the error correction compensates for the obscured modules.
How to Generate a QR Code
- Type or paste the text you want to encode — most commonly a full URL beginning with https://.
- The QR code preview updates automatically as you type.
- Once the content looks right, click the download button to save the code as a PNG.
- Test the code with your phone camera before publishing it. A small shift in contrast or size can make the difference between a code that scans instantly and one that frustrates users.
Examples
Simple URL
Input
https://example.com
URLs are the most common QR payload. Keep them short — longer URLs produce denser codes that are harder to scan at a distance.
Wi-Fi network
Input
WIFI:T:WPA;S:GuestNetwork;P:welcome123;;
A phone scanning this code can offer to join the network directly. Useful for cafés, offices, and printed signs.
Contact card
Input
BEGIN:VCARD VERSION:3.0 FN:Ada Lovelace TEL:+44 20 7946 0958 EMAIL:ada@example.com END:VCARD
Scanning adds the contact to the phone's address book. Great for business cards or conference badges.
Common Use Cases
- Linking a printed poster, flyer, or packaging to an online product page.
- Sharing a Wi-Fi password with guests without having them type a long string.
- Putting a quick-join link on a meeting room door.
- Tracking campaigns with a unique URL per printed piece — scans roll up cleanly in analytics.
- Encoding payment requests (e.g., cryptocurrency addresses, merchant QR codes for local payment systems).
Tips
- Use a URL shortener if your target is a long, ugly URL with tracking parameters — the resulting QR code will be smaller and much easier to scan.
- Test at the actual size you plan to print. A code that scans at 10 cm may not scan at 1 cm. A conservative rule of thumb is a minimum printed size of 2 × 2 cm and a scan distance roughly 10 times the code width.
- Keep high contrast between foreground and background — dark on light is the default and scans best. Very light colours on white, or reversed colours, tend to fail.
- Always include a human-readable URL nearby as a fallback for anyone who cannot scan the code.
Frequently Asked Questions
Do QR codes expire?
The code itself does not — it is just an image encoding a string. But the URL it points to can go stale. If you print codes for long-lived material, point them at a redirect URL you control so you can update the destination later without reprinting.
What is the maximum amount of data I can put in a QR code?
In theory a single QR code can hold up to around 4,000 characters, but practical codes are much shorter. The more data you encode, the denser the pattern becomes and the harder it is to scan. Aim for under 200 characters whenever possible.
Can I add a logo in the middle of the code?
Yes, as long as the logo covers less than about 20–25% of the code's area and you choose a high error-correction level. Always rescan the finished code to confirm it still works.
Why do some codes have rounded corners or coloured dots?
The QR specification only mandates a certain pattern of dark and light modules. Designers are free to render those modules as rounded shapes, circles, or branded patterns — scanners read the overall geometry, not the exact visual style.
Is my input sent to a server?
No. The QR code is generated entirely in your browser. Private URLs, tokens, and contact details never leave your device.