Bing and Copilot: the channel nobody optimises for
Copilot is small and cheap to reach, which is a better combination than it sounds. It carried 3.51 percent of AI referrals in 2026, but it draws on the Bing index, where you can push a new page instead of waiting to be crawled. IndexNow accepts up to 10,000 URLs per request and costs nothing.
The case for a 3.51 percent channel
By volume Copilot barely registers. Measured across 101,574 websites it carried 3.51 percent of AI referrals in 2026, against ChatGPT at 74.78 percent, Gemini at 11.56 percent and Perplexity at 7.23 percent. On those numbers alone nobody would build a plan around it.
The reason to care is what sits underneath. Copilot draws on the Bing index, and Bing is a far less crowded room than Google's. For a local business with a new page, the practical difference is that you can announce the page rather than wait for it to be discovered, and the announcement channel is free.
IndexNow, exactly as documented
IndexNow lets a site notify participating search engines when URLs are added, updated or deleted. Engines that adopt the protocol agree that submitted URLs are automatically shared with all other participating engines, so one notification travels further than the one engine you sent it to.
The mechanics are small. You may submit up to 10,000 URLs per post. The key is a string of 8 to 128 hexadecimal characters, letters, numbers and dashes only, and you host it as a UTF-8 text file at your domain root. That is the entire setup, and it is a one time job.
| Platform | Share of AI referrals | Underlying index |
|---|---|---|
| ChatGPT | 74.78 % | Own crawl, OAI-SearchBot |
| Gemini | 11.56 % | |
| Perplexity | 7.23 % | Own crawl |
| Copilot | 3.51 % | Bing |
| Claude | 2.62 % | Own crawl |
What it does not promise
The documentation is honest in a way that most tools are not. An HTTP 200 response code only indicates that the search engine has received your URL. It is a receipt, not an index entry, and certainly not a ranking. Anyone selling IndexNow as a ranking tactic is selling a delivery confirmation.
Used correctly it removes one specific delay: the gap between publishing and being discovered. That is worth having for a business whose pages change, opening hours, seasonal offers, a new location, and worth nothing at all for a site that never changes.
Questions and answers
Is it worth optimising for 3.51 percent?
How many URLs can I submit at once?
Does IndexNow get me indexed faster?
Do I need a separate key for each search engine?
Sources
- IndexNow documentation Limits, key format and the statement that HTTP 200 means receipt only
- SE Ranking, AI traffic research study, 18 June 2026 101,574 websites; platform shares of AI referrals
