BIN Lookup API Integration: Developer's Complete Guide (2026)

# JavaScript (Node.js)
npm install axios dotenv

# Python
pip3 install requests python-dotenv

# PHP
composer require guzzlehttp/guzzle vlucas/phpdotenv

async function validateCardList(cards) {
  const bins = cards.map(card => card.number.substring(0, 8));

  // Split into chunks of 50
  const chunks = [];
  for (let i = 0; i < bins.length; i += 50) {
    chunks.push(bins.slice(i, i + 50));
  }

  const results = [];

  for (const chunk of chunks) {
    const batchResult = await client.batchLookup(chunk);
    results.push(...batchResult.results);
  }

  return results;
}

async function lookupWithRetry(binNumber, maxRetries = 3) {
  let retries = 0;
  let delay = 1000; // Start with 1 second

  while (retries < maxRetries) {
    try {
      return await client.lookup(binNumber);
    } catch (error) {
      if (error.message.includes('Rate limit exceeded') && retries < maxRetries - 1) {
        retries++;
        console.log(`Rate limited. Retrying in ${delay}ms...`);
        await new Promise(resolve => setTimeout(resolve, delay));
        delay *= 2; // Exponential backoff
      } else {
        throw error;
      }
    }
  }
}

const NodeCache = require('node-cache');
const cache = new NodeCache({ stdTTL: 3600 }); // 1 hour TTL

async function cachedLookup(binNumber) {
  // Check cache first
  const cached = cache.get(binNumber);
  if (cached) {
    console.log('Cache hit for', binNumber);
    return cached;
  }

  // Not in cache, make API call
  console.log('Cache miss for', binNumber);
  const result = await client.lookup(binNumber);

  // Store in cache
  cache.set(binNumber, result);

  return result;
}

async function handleCardInput(cardNumber) {
  // Extract BIN (first 6-8 digits)
  const bin = cardNumber.replace(/\s/g, '').substring(0, 8);

  if (bin.length < 6) {
    return { valid: false, message: 'Enter at least 6 digits' };
  }

  try {
    const result = await cachedLookup(bin);

    if (!result.success) {
      return { valid: false, message: 'Could not validate card' };
    }

    const cardData = result.data;

    // Check if we accept this card type
    const acceptedBrands = ['VISA', 'MASTERCARD', 'AMEX'];
    if (!acceptedBrands.includes(cardData.Brand)) {
      return {
        valid: false,
        message: `Sorry, we don't accept ${cardData.Brand} cards`
      };
    }

    // Success
    return {
      valid: true,
      brand: cardData.Brand,
      type: cardData.Type,
      issuer: cardData.Issuer,
      country: cardData.CountryName
    };

  } catch (error) {
    // Don't block checkout if API fails
    return {
      valid: true,
      warning: 'Could not verify card details'
    };
  }
}

async function runTests() {
  const client = new BinSearchClient(config.apiKey, config.userId);

  console.log('Test 1: Valid BIN lookup');
  const result1 = await client.lookup('559994');
  console.log('Success:', result1.success);

  console.log('\nTest 2: Batch lookup');
  const result2 = await client.batchLookup(['60600508', '655058', '52780726']);
  console.log('Processed:', result2.summary.successful);

  console.log('\nTest 3: Quota check');
  const quota = await client.getQuota();
  console.log('Remaining:',
    quota.limits.requestsPerMonth - quota.usage.requestsThisMonth);

  console.log('\nAll tests passed!');
}