IndexNow: telling Bing before it asks
It is a notification, not a request to rank. One HTTP post carrying up to 10,000 URLs tells participating engines that those pages changed, and a 200 response only means the submission was received. That is the whole protocol, and its value is speed rather than favour.
What the protocol actually is
IndexNow replaces waiting with telling. Instead of hoping a crawler returns, you post a list of changed URLs to an endpoint and the participating engines are informed. It says nothing about quality and promises nothing about position. It removes a delay, and that is all.
The authentication is deliberately primitive. You publish a text file named after your key at the root of your host, and the post refers to it. If the file is reachable and the contents match, the submission is attributed to you.
The specification, in numbers
The key is 8 to 128 characters and may contain lowercase letters, uppercase letters, digits and dashes. One post may carry up to 10,000 URLs, and http and https may be mixed in the same list.
The response codes are the part worth learning, because they are routinely misread. 200 means the URL was submitted successfully. 202 means it was received and key validation is still pending. 400 is a bad request, 403 means the key is invalid or not found, 422 means the URLs do not belong to the host or the key schema does not match, and 429 means you look like spam. None of them is a statement about indexing.
One detail catches people out. The key file's location defines its scope: a key at a subdirectory can only cover URLs beginning with that path. Put the file at the root unless you have a reason not to, and submit only URLs on the same host, or you will collect 422 responses.
| Code | Meaning | What to do |
|---|---|---|
| 200 | Submitted successfully | Nothing |
| 202 | Received, key validation pending | Check the key file is reachable |
| 400 | Bad request, invalid format | Fix the payload |
| 403 | Key invalid or not found | Republish the key file |
| 422 | URLs not on this host, or key mismatch | Filter the list by host |
| 429 | Too many requests | Reduce frequency |
Why bother at all
Because the Bing family delivers real visitors on these sites. In our own measurement across this network the Bing index family accounted for 344 human visits against 273 from Google, which is the opposite of the usual assumption and the reason IndexNow gets priority here.
Set it up once, on publish. A hand run submission after a big change is worth little, an automatic post on every publish costs nothing after the first afternoon.
Questions and answers
Does IndexNow improve ranking?
How many URLs can I send?
Why do I get 422?
Does Google use it?
Sources
- IndexNow, protocol documentation Key format, the 10,000 URL limit, response codes and key scope
- Google Search Central, Sitemaps overview The alternative mechanism, and when a site needs one at all
