WhatsApp: what it is and how to block or allow it

What WhatsApp does

When someone types or pastes a link into a WhatsApp chat, WhatsApp fetches the page on the sender's behalf and reads its Open Graph tags to show a preview. Meta's documentation doesn't mention robots.txt.

• The Open Graph tags must be in the first 300 KB of the HTML, and the preview image under 600 KB and at least 300 pixels wide. Source
• The request carries the recipient's language in its Accept-Language header, so you can localize the preview. Source

Does WhatsApp follow robots.txt?

Meta doesn't say whether WhatsApp follows robots.txt.

How to stop WhatsApp

Meta documents no robots.txt name for WhatsApp previews. Blocking its user agent on your server stops the preview.

What blocking WhatsApp changes

Links to your site are sent as plain URLs, without a preview.

Where to see WhatsApp visits

Most bots never appear in Google Analytics. Many don't run JavaScript, so the analytics tag never loads, and Google Analytics 4 automatically excludes traffic from known bots and spiders. Your server or CDN logs record every request with its user agent, so search them for the bot's name.

OneLence recognizes WhatsApp and keeps it out of your visitor counts. With Premium, bot traffic shows which bots visit your site, how often and what kind they are.

Other bots from Meta

• Meta-ExternalFetcher: Fetches links at a user's request, including for Meta AI. Meta says it may bypass robots.txt.
• Meta-WebIndexer: Improves Meta AI's search results, so Meta AI can cite and link to your pages.
• Meta-ExternalAgent: Crawls the web for uses such as training Meta's foundation AI models.
• FacebookExternalHit: Fetches pages shared on Facebook, Instagram or Messenger to build their link previews.