QR Code Generator
Type what you want encoded and download the QR code as an image. Includes UPI payment codes and WiFi codes, and it all happens in your browser so nothing is uploaded.
What a QR code actually is
A QR code is text, encoded as a grid. That is the whole idea. Scanning one does not fetch anything from a server. It reads characters, and your phone then decides what to do with them based on how they start. Text beginning with https:// is offered as a link. Text beginning with upi://pay opens a payment app. Text beginning with WIFI: offers to join a network.
This matters for two reasons. First, a QR code cannot be changed after it is printed, because the data is the pattern. Second, a QR code can point anywhere, and you cannot tell where by looking at it, which is the basis of most QR fraud.
Error correction, and why codes still scan when damaged
Every QR code carries redundant data. At the medium level used here, roughly 15 percent of the code can be obscured, scratched or printed badly and it will still read. That is why a sticker with a scuff still works, and it is why you can place a small logo in the centre of a code without breaking it.
The trade off is size. More error correction means a denser grid for the same content. Medium is the sensible default for almost everything.
UPI payment codes
A UPI QR code is a short string containing the payee address, the name, and optionally an amount. Leave the amount blank and the payer types it, which is what you want for a shop counter. Fill it in and the amount is fixed, which is what you want for a specific invoice.
Two things worth doing before you print anything.
- Test it with a small payment. One rupee to yourself confirms the UPI ID is right and the name displays correctly. A typo in a printed code is expensive to discover later.
- Check the name your payer sees. Their app shows the name registered against your UPI ID, not the one typed here. If those differ, customers hesitate, and hesitating at a payment screen is bad for business.
A word on QR safety
Because you cannot see a destination by looking at a code, scanning one from an unknown source is genuinely risky. Fraud in India commonly works by persuading someone that scanning a code will receive money. It will not. Scanning a UPI QR code initiates a payment from you, never to you. Nobody sending you money needs you to scan anything.
Stickers placed over legitimate codes at shops and parking meters are also common. If a code looks like it has been applied on top of something else, do not use it.
Printing codes that actually scan
- Keep the quiet zone. The white margin around the code is part of the code. Cropping it tight is the most common reason a printed code fails.
- Minimum practical size is about 2 by 2 centimetres for a short link at normal reading distance. A code on a poster read from three metres needs to be far larger.
- Dark on light, always. Inverted codes fail on many scanners.
- Shorten long links first. Fewer characters means a coarser grid, which scans faster and survives worse printing.
- Test on a cheap phone, not just a new one. Older cameras are the real constraint.
Common questions
Do QR codes expire?
Not the ones made here. The data is the pattern, so the code works forever. What can stop working is the destination, so a code pointing at a page you delete becomes a code pointing at a dead page. Commercial dynamic QR services add a redirect in the middle, which is what expires when you stop paying them.
Is my data uploaded to make the code?
No. The code is generated by JavaScript running in your browser. Nothing is transmitted, including UPI IDs and WiFi passwords.
Can someone send me money by scanning my QR code?
No, and this is the basis of a very common fraud in India. Scanning a UPI QR code always starts a payment from the person scanning. If anyone asks you to scan a code to receive money, you are being defrauded.
How small can I print a QR code?
About 2 by 2 centimetres for a short link read at arm's length. Keep the white margin around it intact, since that quiet zone is part of what the scanner needs. Bigger is always safer.
Can I put my logo in the middle?
Usually yes. Error correction tolerates roughly 15 percent of the code being obscured at the level used here. Keep the logo small, centred, and test it on more than one phone before printing a thousand of them.
Why did my code stop scanning after I resized it?
Almost always the quiet zone was cropped, or the image was scaled with smoothing that blurred the module edges. Download at the size you need rather than resizing afterwards.