# QR codes and barcodes API

> QR codes, UPI payment QR codes and barcodes as SVG or PNG.

Generates codes; it does not read them. What you encode is never logged or kept, and the images are not cached by shared caches.

Base URL `https://api.dharun.dev`. No API key. Answers are JSON, `{ "data": ..., "meta": { ... } }`, and errors are `{ "error": { "code", "message" } }` with a matching HTTP status. Rate limit: 600 requests a minute per client.

## QR code for any text

`GET /v1/qr`, also `POST`

Returns the image itself. Text up to about 2,900 bytes at error correction L.

POST body: The text to encode. Send it as `text/plain`, or as JSON `{"text": "..."}` with the other options beside it.

What you send is never written to the log, and the answer is not cached.

Parameters:

- `text` (query): Text to encode (or POST it).
- `ecc` (query): Error correction: how much damage the code survives. Default M. One of: L, M, Q, H.
- `format` (query): Image format. Default svg. One of: svg, png.
- `size` (query): 2D codes: width in pixels to stay within, 32 to 2048. Default 256.
- `margin` (query): Light border (quiet zone), in modules, 0 to 16. Default 4.
- `fg` (query): Dark colour, hex such as 000000. Default black.
- `bg` (query): Light colour, hex, or transparent. Default white.

Example: https://api.dharun.dev/v1/qr?text=https://api.dharun.dev&format=png&size=256 (returns the image itself)

## UPI payment QR code

`GET /v1/upi-qr`

A QR code any UPI app can scan to pay, built to NPCI's upi://pay link format. format=json returns the link instead of the image. Nothing is checked with a bank.

What you send is never written to the log, and the answer is not cached.

Parameters:

- `pa` (query, required): Payee UPI ID, such as shop@okaxis.
- `pn` (query): Payee name shown in the app.
- `am` (query): Amount in rupees, up to two decimals. Leave out to let the payer type it.
- `tn` (query): Note shown with the payment, up to 80 characters.
- `tr` (query): Your reference for the transaction.
- `mc` (query): Merchant category code, four digits.
- `format` (query): Image format. Default svg. One of: svg, png.
- `size` (query): 2D codes: width in pixels to stay within, 32 to 2048. Default 256.
- `margin` (query): Light border (quiet zone), in modules, 0 to 16. Default 4.
- `fg` (query): Dark colour, hex such as 000000. Default black.
- `bg` (query): Light colour, hex, or transparent. Default white.

Example: https://api.dharun.dev/v1/upi-qr?pa=shop@okaxis&pn=Sri%20Murugan%20Stores&am=250&tn=Order%2042 (returns the image itself)

## Barcode

`GET /v1/barcode/{type}`, also `POST`

Linear barcodes (code128, code39, code93, ean13, ean8, itf, codabar) and 2D codes (datamatrix, pdf417, aztec). Linear codes are sized with scale and height, 2D codes with size. No human-readable text is printed under the bars.

POST body: The text to encode. Send it as `text/plain`, or as JSON `{"text": "..."}` with the other options beside it.

What you send is never written to the log, and the answer is not cached.

Parameters:

- `type` (path, required): Kind of barcode. One of: code128, code39, code93, ean13, ean8, itf, codabar, datamatrix, pdf417, aztec.
- `text` (query): Text to encode (or POST it).
- `scale` (query): Linear codes: pixels per bar module, 1 to 10. Default 2.
- `height` (query): Linear codes: bar height in pixels, 10 to 600. Default 80.
- `format` (query): Image format. Default svg. One of: svg, png.
- `size` (query): 2D codes: width in pixels to stay within, 32 to 2048. Default 256.
- `margin` (query): Light border, in modules, 0 to 16. The default depends on the code.
- `fg` (query): Dark colour, hex such as 000000. Default black.
- `bg` (query): Light colour, hex, or transparent. Default white.

Example: https://api.dharun.dev/v1/barcode/ean13?text=890123456789 (returns the image itself)

## Guides

- [Make a UPI payment QR code for an amount](https://api.dharun.dev/guides/upi-qr-code.md): Generate a QR code that any UPI app can scan to pay a set amount to your UPI ID, or a upi://pay link for a button on mobile.