SnapOtter/apps/docs/tools/image/qr-generate.md

description

description
Generate QR codes with custom colors and error correction levels.

QR Code Generator

Generate QR code images from text or URLs with configurable size, error correction level, and custom foreground/background colors.

API Endpoint

POST /api/v1/tools/image/qr-generate

Accepts a JSON body (not multipart). No file upload is needed.

Parameters

Parameter	Type	Required	Default	Description
text	string	Yes	-	Content to encode in the QR code (1 to 2000 characters)
size	number	No	400	Output image width/height in pixels (100 to 10000)
errorCorrection	string	No	"M"	Error correction level: L (7%), M (15%), Q (25%), H (30%)
foreground	string	No	"#000000"	QR code foreground/module color in hex (#RRGGBB)
background	string	No	"#FFFFFF"	QR code background color in hex (#RRGGBB)
logoDataUri	string	No	-	Logo image as a data URI (data:image/png;base64,... or data:image/jpeg;base64,..., max 700 KB). Centered on the QR code at 22% of the QR size. Forces error correction to H

Error Correction Levels

Level	Recovery	Use Case
L	~7%	Maximum data density
M	~15%	Balanced (default)
Q	~25%	Good for printed codes
H	~30%	Best for codes with logos overlay

Example Request

curl -X POST http://localhost:1349/api/v1/tools/image/qr-generate \
  -H "Authorization: Bearer si_your-api-key" \
  -H "Content-Type: application/json" \
  -d '{"text": "https://snapotter.com", "size": 500, "errorCorrection": "H"}'

Branded QR code with custom colors:

curl -X POST http://localhost:1349/api/v1/tools/image/qr-generate \
  -H "Authorization: Bearer si_your-api-key" \
  -H "Content-Type: application/json" \
  -d '{"text": "Hello World", "size": 300, "foreground": "#1a365d", "background": "#f7fafc"}'

Example Response

{
  "jobId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "downloadUrl": "/api/v1/download/a1b2c3d4-e5f6-7890-abcd-ef1234567890/qrcode.png",
  "originalSize": 0,
  "processedSize": 4520
}

Notes

• This endpoint accepts JSON, not multipart form data, since no image upload is needed.
• The output is always a PNG image.
• The output filename is always qrcode.png.
• originalSize is always 0 since this tool generates images from scratch.
• A 2-module quiet zone (margin) is included around the QR code.
• Maximum text length is 2000 characters. Actual capacity depends on error correction level and character encoding.
• Higher error correction levels allow the QR code to remain scannable even if partially obscured but reduce data capacity.
• When a logoDataUri is provided, error correction is automatically forced to H (30%) so the QR code remains scannable despite the logo occluding the center.