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IndexNow is an open protocol that tells search engines immediately that a page has changed. Answer engines
What is IndexNow?
IndexNow is an open protocol that tells search engines immediately that a page has changed.
Classic discovery rests on waiting: the page is published and you wait for the crawler to come by. IndexNow reverses that — the moment the page is published a notification is sent to the engine and the crawler is called.
Setting it up takes three steps: a key is generated, a text file containing that key is placed at the site root, and changed addresses are submitted to an endpoint. The engine verifies that the notification really comes from the site owner by reading the key file from the LIVE site.
That verification also fixes the running order: the notification has to be sent AFTER DEPLOYMENT. If the key file is not published yet, verification fails and the notification is rejected.
The Bing and Yandex family support it; Google does not, and has said so plainly. In the context of answer engines its value comes through Bing — Microsoft’s answer product is fed by the Bing index.
The most common mistake is submitting every address on every deployment. That turns the “this page really changed” signal the notification carries into noise. A correct setup requires a mechanism that knows which page actually changed.
The return varies by type of site. For a frequently updated publication, shortening the discovery delay is a real gain; on a corporate site updated a few times a year the practical benefit is small.
That the key sits openly at the root is not a security hole but the design itself: verification is only possible while the file is public. Someone who knows the key can only send the information “this page changed”, and there is no value in abusing that.
- Generate the key and keep it — generated once, never changed.
- Put the key file at the root — let it come out of the build, so it is not forgotten by hand.
- Notify AFTER deployment — reverse the order and verification fails.
- Submit only what really changed — submitting every address on every build devalues the signal.
- Watch the outcome — notification records appear in the engine’s webmaster panel.
The fourth item is the rule of the protocol most often broken: the information a notification carries is “this page really changed”, and a signal that reports everything turns into a signal that reports nothing.
Calibrating expectations matters: IndexNow speeds up discovery, it does not guarantee indexing. If a page is crawled quickly and found to be poor, it still will not be indexed. For a site with indexing problems the answer is not this protocol but content quality, and that has to be addressed first.
Where the protocol genuinely makes a difference is elsewhere: on large, frequently updated sites it affects when a crawler returns to which address, that is, on the crawl budget side.
If you want to know how your brand is cited in ChatGPT, Google AI Overviews and Perplexity, our GEO consulting records which questions and engines cite you and builds the prerequisites.
Answer engines
INP (Interaction to Next Paint) is the time from a user interaction until the page responds visually, and Google counts anything under 200 milliseconds as good. Performance
J
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L
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R
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S
Screen reader A screen reader is assistive technology that turns on-screen content into speech or braille output and lets the user navigate by keyboard. Accessibility
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T
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TTFB (Time to First Byte) is the time between the browser sending a request and receiving the first byte from the server. Performance
W
WCAG (Web Content Accessibility Guidelines) is the international standard published by the W3C that defines the accessibility of web content through testable success criteria. Accessibility
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x-default is a special hreflang value declaring the default page to show when no language version matches the user’s language. Multilingual