In October 2021, Microsoft Bing introduced a new protocol called IndexNow, designed to modernize how search engines discover and index web content. Rather than waiting for traditional web crawlers to check for updates periodically, IndexNow allows site owners to instantly notify search engines whenever content is added, updated, or deleted.
This real-time signaling dramatically shortens the lag between publishing and indexing. This innovation has significant implications for Bing’s search engine and the way conversational AI systems like ChatGPT find and surface content.
This connection is more important than it might seem at first glance. When ChatGPT is browsing the web, it relies on Bing’s infrastructure to perform searches and retrieve content. That means the faster your site is indexed in Bing, the more likely your content will be found, cited, or summarized in a ChatGPT response. Implementing IndexNow is no longer just about search engine optimization—it’s about AI visibility.
This article explains how IndexNow works and how it connects to ChatGPT’s browsing capability. It also provides a hands-on PHP implementation for registering your site and pushing content updates.
Table of ContentsWhat is IndexNow and Why Should You Care?How IndexNow WorksHow to Request an IndexNow KeyGenerate KeyRequest KeyHow to Use IndexNow (PHP Example)Notify Bing of New ContentNotify Bing of Removed ContentChatGPT and Bing: Why Fresh Indexing Matters
What is IndexNow and Why Should You Care?
IndexNow is an open-source protocol pioneered by Microsoft Bing and now supported by Yandex and other engines. Rather than waiting for search bots to crawl your site periodically, you notify search engines in real time when content is added, updated, or deleted. This is especially useful for high-frequency publishers, e-commerce sites, or anyone wanting to reduce the lag between publishing and visibility.
Why this matters now more than ever: ChatGPT’s real-time web browsing feature, powered by Bing, increasingly sources information from freshly indexed content. Using IndexNow means your latest content might appear in AI answers sooner, potentially within minutes.
How IndexNow Works
IndexNow is straightforward. When content at a URL is published or updated, your server sends a simple HTTP request to the IndexNow API, including:
Your unique API key (proving your identity)
The updated URL(s)
An endpoint that Bing and other engines monitor
No crawling delays. No search console submissions. Just instant discoverability.
How to Request an IndexNow Key
To use IndexNow, you need a valid key that confirms you control the site. There are two supported methods for obtaining a key:
Generate Key
This is the most common and recommended approach for individual site owners. Generate a 128-bit key and convert it to a 32-character hexadecimal string (e.g., a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5). Create a plain text file named exactly as the key and place it at the root of your website, like so:
https://yoursite.com/a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5.txt
The file’s contents should be the key with no whitespace or additional formatting. Here’s a PHP snippet to generate the key and save the file:
// Generate 128-bit key
$key = bin2hex(random_bytes(16));
// Save to your site’s root directory file_put_contents(__DIR__ . “/$key.txt", $key);
echo "Generated IndexNow key: $key\n";
Request Key
Go to Bing’s IndexNow Page and request a key (e.g., a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5).
Add it to a file named after the key with a .txt extension. Be sure not to have any line returns in the file.
Upload it to your website’s root directory.
Verify that you can see the file publicly by navigating to:
https://yoursite.com/a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5.txt
Update the key and file name with your own, of course.
Once this file is live and publicly accessible, you can submit URLs to Bing using that key.
How to Use IndexNow (PHP Example)
Once you’ve created your key and published the verification file, you can start submitting URLs.
Notify Bing of New Content
Here’s a basic PHP script to notify Bing when you update or publish content:
$host,
‘key’ => $key,
‘keyLocation’ => "https://$host/$key.txt",
‘urlList’ => $urls
]);
$ch = curl_init($endpoint);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, [‘Content-Type: application/json’]);
curl_setopt($ch, CURLOPT_POSTFIELDS, $payload);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$response = curl_exec($ch);
$httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
curl_close($ch);
if ($httpCode === 200) {
echo "IndexNow submission successful.\n";
} else {
echo "IndexNow submission failed with status code $httpCode.\n";
echo "Response: $response\n";
}
}
// Example usage
$urlsToNotify = [
‘https://yoursite.com/blog/new-post-title’,
‘https://yoursite.com/products/widget-update’
];
sendToIndexNow($urlsToNotify, ‘yoursite.com’, ‘a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5’);
?>
This script can be triggered whenever you publish new content, update an existing post, or delete a page. You can integrate it into your CMS’s post-publish hook or batch submit recent changes on a schedule.
Notify Bing of Removed Content
The IndexNow API doesn’t explicitly require you to declare that a URL is being deleted. Instead, when you notify the endpoint about a URL that no longer exists (i.e., it returns a 404 or 410 HTTP status code when crawled), Bing and other participating search engines will treat the notification as a removal signal.
ChatGPT and Bing: Why Fresh Indexing Matters
OpenAI’s ChatGPT relies on Bing’s index to retrieve information in real time when web browsing is enabled. Unlike search engine bots that may take hours or days to discover a new page, IndexNow can notify Bing in seconds. This means:
Faster exposure to AI-generated responses: Your content has a greater chance of being used in ChatGPT summaries, links, or citations
Better freshness ranking: Bing prioritizes recently updated content for retrieval-based answers
For businesses aiming to stay visible in search engines and conversational AI platforms like ChatGPT, IndexNow is a lightweight but powerful tool. It reduces the gap between publishing and visibility, aligning your content strategy with the shift toward AI-driven discovery.
By implementing a simple PHP script and registering your site key, you can dramatically improve the freshness and discoverability of your content across Bing and ChatGPT.
If you’re running WordPress, the Rank Math plugin and most other SEO WordPress Plugins already have IndexNow integrated and enabled. I’d highly recommend that you review the settings, though. For example, WooCommerce sites will likely need to enable products to be included.
Along with Microsoft Bing, Yandex, Naver, Seznam.cz, and Yep have APIs that receive IndexNow requests to process website content updates.
©2025 DK New Media, LLC, All rights reserved | DisclosureOriginally Published on Martech Zone: Unlocking AI Visibility: How Bing IndexNow Helps Brands Boost ChatGPT Discoverability