API Documentation

Everything you need to make your first request.

Authentication

Required

Every request must include your API key in the Authorization header as a bearer token. Keys are created from the API Keys page.

auth.js

node.js

const CARDIENT_API_KEY = process.env.CARDIENT_API_KEY;

const response = await fetch("https://api.cardient.dev/v1/lookup", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${CARDIENT_API_KEY}`,
    "Content-Type": "application/json"
  },
  body: JSON.stringify({ cardNumber: "4539418765210012" })
});

Request example

Send a POST request with the card number in the JSON body.

lookup.js

node.js

// lookup.js
const response = await fetch("https://api.cardient.dev/v1/lookup", {
  method: "POST",
  headers: {
    "Authorization": "Bearer ck_live_your_api_key",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    cardNumber: "4539418765210012"
  })
});

const data = await response.json();
console.log(data);

Response example

A successful lookup returns the bank, country and network as JSON.

response.json

json

// 200 OK
{
  "bank": {
    "name": "Chase Bank",
    "logo": "https://cdn.cardient.dev/logos/chase.svg"
  },
  "country": {
    "name": "United States",
    "code": "US"
  },
  "network": "Visa",
  "bin": "453941"
}

Error example

Errors are returned with a matching HTTP status code and a consistent shape.

errors.json

json

// 401 Unauthorized — missing or invalid API key
{
  "error": {
    "code": "invalid_api_key",
    "message": "The API key provided is invalid or has been revoked."
  }
}

// 422 Unprocessable Entity — malformed card number
{
  "error": {
    "code": "invalid_card_number",
    "message": "The cardNumber field must contain 12-19 digits."
  }
}

Looking for other languages? Node.js examples are available now — Python, Ruby and PHP examples are planned for a future release.