QR Code API Documentation

Generate QR codes with a simple REST API. Free, no API key required, and CORS-enabled for browser use. Up to 100 requests per hour.

Base URL

https://nofolo.com/api/qr/generate

Authentication (Optional)

The API works without authentication at 100 requests/hour per IP. For higher limits (1,000 req/hr), create a free API key from your dashboard.

# With API key (1,000 req/hr)
curl "https://nofolo.com/api/qr/generate?data=hello" \
  -H "Authorization: Bearer nf_live_your_key_here"

# Without API key (100 req/hr) — no header needed
curl "https://nofolo.com/api/qr/generate?data=hello"

Tier	Rate Limit	Auth Required
Free (no key)	100 requests/hour per IP	No
API Key	1,000 requests/hour	`Authorization: Bearer nf_live_...`

GETGenerate QR Code

Generate a QR code image by passing parameters as query strings. Returns a PNG image by default, or SVG if specified.

GET /api/qr/generate?data=https://example.com&size=300&color=%231F4E79

Parameters

Parameter	Type	Default	Description
data*	string	—	Required. The text or URL to encode in the QR code. Max 4,296 characters.
format	string	png	Output format: png or svg.
size	number	300	Image width/height in pixels. Range: 50–2000.
margin	number	4	Quiet zone margin in modules. Range: 0–20.
color	string	#1F4E79	Foreground color (hex). e.g. %231F4E79 or 1F4E79.
bgColor	string	#FFFFFF	Background color (hex).
ec	string	M	Error correction level: L (7%), M (15%), Q (25%), H (30%).
output	string	—	Set to json to return a JSON object with a data URL instead of raw image.

POSTGenerate QR Code (JSON)

Send a JSON body for more complex data. Always returns a JSON response with a base64 data URL.

POST /api/qr/generate
Content-Type: application/json

{
  "data": "https://example.com",
  "format": "png",
  "size": 400,
  "color": "#1F4E79",
  "bgColor": "#FFFFFF",
  "ec": "H"
}

Response

{
  "data": "data:image/png;base64,iVBORw0KGgo...",
  "format": "png",
  "size": 400,
  "ec": "H"
}

Code Examples

cURL

# Download as PNG
curl -o qr-code.png "https://nofolo.com/api/qr/generate?data=https://example.com&size=400"

# Get as SVG
curl -o qr-code.svg "https://nofolo.com/api/qr/generate?data=https://example.com&format=svg"

# POST with JSON body
curl -X POST https://nofolo.com/api/qr/generate \
  -H "Content-Type: application/json" \
  -d '{"data":"https://example.com","size":400,"color":"#1F4E79","ec":"H"}'

JavaScript

// Display QR code as an image
const img = document.createElement('img');
img.src = 'https://nofolo.com/api/qr/generate?data=https://example.com&size=300';
document.body.appendChild(img);

// Or fetch as JSON with data URL
const res = await fetch('https://nofolo.com/api/qr/generate?data=https://example.com&output=json');
const { data } = await res.json();
console.log(data); // "data:image/png;base64,..."

// POST request
const response = await fetch('https://nofolo.com/api/qr/generate', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    data: 'WIFI:T:WPA;S:MyNetwork;P:MyPassword;;',
    size: 400,
    color: '#1F4E79',
    ec: 'H',
  }),
});
const result = await response.json();

Python

import requests

# Download PNG
response = requests.get(
    "https://nofolo.com/api/qr/generate",
    params={"data": "https://example.com", "size": 400}
)
with open("qr-code.png", "wb") as f:
    f.write(response.content)

# POST with JSON
response = requests.post(
    "https://nofolo.com/api/qr/generate",
    json={
        "data": "https://example.com",
        "size": 400,
        "color": "#1F4E79",
        "ec": "H",
    }
)
data_url = response.json()["data"]

HTML (Inline)

<!-- Embed directly in an img tag -->
<img
  src="https://nofolo.com/api/qr/generate?data=https://example.com&size=200"
  alt="QR Code"
  width="200"
  height="200"
/>

Try It Out

Test the API live. Enter your data and see the generated QR code instantly.

Data *

Size

Format

Error Correction

Colors

https://nofolo.com/api/qr/generate?data=https%3A%2F%2Fexample.com&size=300&color=%231F4E79&bgColor=%23FFFFFF&format=png&ec=M

Embeddable Widget

Add a full QR code generator to any website with a single script tag. The widget runs in an iframe and includes input fields, color pickers, and a download button.

<script src="https://nofolo.com/embed.js" data-type="url"></script>

Widget Options (data attributes)

Attribute	Default	Description
data-type	url	QR type: url, text, wifi, email, phone, sms
data-color	1F4E79	Foreground color (hex without #)
data-bg	FFFFFF	Background color (hex without #)
data-width	400	Widget width in pixels
data-height	520	Widget height in pixels

Rate Limits

100 requests/hour (no key) or 1,000 requests/hour (with API key)

The API uses a sliding window rate limiter. Check the X-RateLimit-Remaining response header to monitor your usage. If you exceed the limit, you will receive a 429 status code with a Retry-After header. Create a free API key for 10x higher limits.

Error Responses

Status	Meaning
400	Bad request — missing data parameter, invalid color, or data too long
429	Rate limit exceeded — wait and retry (check Retry-After header)
500	Server error — QR generation failed

Supported QR Data Formats

Pass any of these string formats as the data parameter to generate specialized QR codes:

URL

https://example.com

Plain Text

Hello, world!

WiFi

WIFI:T:WPA;S:MyNetwork;P:MyPass;;

Email

mailto:hi@example.com?subject=Hi

Phone

tel:+1234567890

SMS

sms:+1234567890?body=Hello

Location

geo:40.7829,-73.9654

vCard

BEGIN:VCARD\nVERSION:3.0\n...

https://wa.me/1234567890

Crypto

bitcoin:1A1zP1...?amount=0.01

Frequently Asked Questions

Do I need an API key?

No. The API works without authentication at 100 requests per hour. For higher limits (1,000 req/hr), create a free API key from your Nofolo dashboard.

Can I use this in production?

Yes. The API is CORS-enabled and works from any domain. Without a key it is rate-limited to 100 requests per hour per IP. With an API key you get 1,000 requests per hour.

What is the maximum data length?

QR codes can encode up to 4,296 alphanumeric characters. The API enforces this limit and returns a 400 error if exceeded.

Can I generate QR codes with a logo?

The REST API generates standard QR codes without logos. For custom logos, shapes, and frames, use our visual generator or the qr-code-styling JavaScript library.

Are the generated QR codes static or dynamic?

Static. The API generates the QR code directly from the data you provide — no tracking, no redirect URLs. For dynamic QR codes with scan tracking, use the full Nofolo dashboard.

What error correction level should I use?

M (15%) is the default and works well for most uses. Use H (30%) if the code will be printed small or on textured surfaces. Use L (7%) to maximize data capacity.

Try the Visual QR Code Generator

Not a developer? Use our visual generator — no code required.

Create QR Code