WHOIS API: Faster and More Reliable Lookups, Cleaner WHOIS Data, Same API

TL;DR

• The upgraded WHOIS API runs real-time lookups with improved parsing accuracy.
• It’s now 2x faster than before. 
• Account rate limits now go up to 200 requests per second, up from 50.
• Control the cache freshness and choose the protocol used to retrieve domain registration data.
• Some changes may affect how you integrate.

A major update to our WHOIS API is live — it’s still the same API for obtaining domain registration records, just upgraded to help make your processes smoother.

Get faster, more dependable lookups

These improvements apply automatically to all WHOIS API requests, with no setting to turn on:

• Faster real-time retrieval. When the API needs a live answer from an RDAP or WHOIS server, average end-to-end retrieval runs 2x faster (about 1,000 ms versus 2,000 ms previously). For about 1.1 million frequently requested domains, you can get the results much faster because a fresh record is already cached every 12 hours.
• More complete responses. The average NO_DATA responses went down from 7% to 0.48%, so more of your calls return a usable record on the first try.
• Cleaner structured fields. The newly upgraded parser returns clean fields with 9x fewer parsing errors on affected records (about 2% versus 19% in the past), while keeping the raw source text available alongside the parsed data.

Higher rate limit, more say in how lookups run

You now have a higher rate limit and more control over the protocol used in your lookups and the freshness of cached records. 

• 4x higher rate limit. The account rate limit is now 200 requests per second, up from a 50 requests-per-second ceiling. 
• Fresh data on demand. Set how fresh a cached record needs to be before WHOIS API looks it up again with the maxCacheAgeHours parameter. The minimum refresh window is 24 hours, except for around 1.1 million frequently requested domains which are automatically refreshed every 12 hours.
• Source control. Choose the protocol the tool will use to retrieve domain registration data. Set the rdap parameter to Auto (the API will automatically choose the best data available),  RDAP-only, or WHOIS-only.

Learn more about the parameters here.

A few older options are going away

Most WHOIS API integrations can move to the upgraded tool as-is, except those that rely on older options that are being retired:

• JSONP is no longer available. You can use JSON or XML instead.
• Partial bulk downloads. If your current process involves reading partial bulk files, please make the necessary adjustments to your code because WHOIS API now returns a headers-only CSV until a bulk job is complete.
• Some parameters and session commands have been deprecated. thinWhois, checkProxyData, ipWhois, and other parameters listed here are still accepted, but they no longer affect the tool’s response. The session command cmd=LOGOUT has also been removed.   

Try the upgraded WHOIS API in your account. Get started with 500 free API requests.

Have questions about WHOIS API improvements or want help mapping your migration? Feel free to email WhoisXML API Product Leadership at [email protected] anytime.