ipapi.co vs PostalCodes

ipapi.co geolocates an IP address and returns the result as JSON, XML, or YAML without requiring an API key for light use, though the no-key path is rate-limited and marketed by the vendor as a free trial rather than a permanent free tier. Paid subscriptions start at $15/month (or $12/month billed annually) for 60,000 lookups/month, scaling up to $399/month for 15 million/month.

Postalcodes.info is a free postal-code reference for 123 countries and more than 1.8 million records. No key is needed. The JSON endpoint /api/v1/postal-code/{country}/{code} returns the place name, region and coordinates for one code. Per-country exports come as CSV, JSON or XLSX. The JSON API sends Access-Control-Allow-Origin: *, so a browser can call it directly. The /search autocomplete endpoint does not send that header.