Free Developer API

Business Card Size Checker API

Check business card dimensions and print quality programmatically. No authentication, no signup, completely free.

← Try the interactive tool • OpenAPI Spec

Endpoint

POST https://businesscards.io/tools/api/business-card-size-check

Authentication: None required
Rate Limit: 2 requests/second per IP
Max File Size: 25 MB

Request

Send a multipart/form-data POST with an image file.

Parameter	Type	Description
image	File (required)	Business card image. Accepted formats: PNG, JPEG, WebP, TIFF.

Example

curl -X POST https://businesscards.io/tools/api/business-card-size-check \
  -F "image=@my-card.png"

Response 200 OK

{
  "file_name": "my-card.png",
  "file_size_bytes": 2457600,
  "width_px": 1050,
  "height_px": 600,
  "aspect_ratio": 1.75,
  "standards": [
    {
      "name": "US Standard",
      "dimensions": "3.5\" × 2\"",
      "aspect_ratio_match": true,
      "estimated_dpi": 300,
      "status": "perfect_match"
    },
    {
      "name": "EU / ISO 7810",
      "dimensions": "85mm × 55mm",
      "aspect_ratio_match": false,
      "estimated_dpi": 277,
      "status": "aspect_ratio_mismatch"
    },
    {
      "name": "Japanese",
      "dimensions": "91mm × 55mm",
      "aspect_ratio_match": false,
      "estimated_dpi": 269,
      "status": "aspect_ratio_mismatch"
    }
  ],
  "print_quality": {
    "estimated_dpi": 300,
    "print_ready": true,
    "high_quality": false,
    "minimum_usable": true
  }
}

Response Fields

Top-level

file_name	Original filename of the uploaded image
file_size_bytes	File size in bytes
width_px	Image width in pixels (larger dimension)
height_px	Image height in pixels (smaller dimension)
aspect_ratio	Width-to-height ratio (e.g. 1.75)

standards[]

name	Standard name (US Standard, EU / ISO 7810, Japanese)
aspect_ratio_match	Whether the image matches this standard's aspect ratio (2% tolerance)
estimated_dpi	Estimated DPI if printed at this standard's size
status	`perfect_match`, `correct_ratio_low_dpi`, `correct_ratio_too_low_res`, or `aspect_ratio_mismatch`

print_quality

estimated_dpi	Estimated DPI based on US standard (3.5" width)
print_ready	true if ≥ 300 DPI
high_quality	true if ≥ 600 DPI
minimum_usable	true if ≥ 150 DPI

Error Responses

400

Bad Request

Missing image parameter, unsupported file type, file exceeds 25 MB, or corrupt image file.

{ "error": "Missing required parameter: image" }

429

Too Many Requests

Rate limit exceeded. Wait and retry. Limit: 2 requests per second per IP address.

CORS

This API supports cross-origin requests. The response includes Access-Control-Allow-Origin: *, so you can call it directly from browser-based applications.

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Use our free interactive tool to drag-and-drop your business card design and see results instantly.

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