Authentication

Authenticate every CompanyData API call with an x-api-key header. The same key powers search, export, and city lookup on app.companydata.com. New accounts get a free trial (150 lookups, no credit card) with 50 requests/second and 100,000 requests/month by default. Compare providers in Choosing a company data API.

API key header

cURL

curl -G "https://app.companydata.com/api/company/search" \
  -H "x-api-key: YOUR_API_KEY" \
  --data-urlencode "countryCode=NL" \
  --data-urlencode "search=Heineken"

Success: HTTP 200 with JSON body (see Quickstart for a full search response example).

Missing or invalid key: HTTP 401:

{
  "message": "Unauthorized",
  "statusCode": 401
}

Never expose API keys in client-side code or public repositories. Use environment variables or a secrets manager in production.

Monthly request limit

Your API key includes 100,000 requests per month by default. Contact support if you need a higher quota.

Rate limit

The API allows 50 requests per second per key. Exceeding the limit returns HTTP 429 Too Many Requests. Retry with exponential backoff.