01 · Operator
Who operates MicrosoftPreview
- Company
- Microsoft Corporation
- Type
- Social preview bot
- Official docs
- bing.com
02 · Behavior
What MicrosoftPreview does
MicrosoftPreview requests a page when a preview of it is needed in Microsoft products. Its user agent contains a Chrome version string. Third-party bot databases list it under Bing's crawler documentation.
03 · Impact
Why MicrosoftPreview matters for your site
If you allow it
- Enables previews of your pages in Microsoft products
- Operated by Microsoft
- Low request volume
If you block it
- Brings no direct search ranking benefit
- You may not want page previews shown
04 · Allow
How to allow MicrosoftPreview
robots.txt
User-agent: MicrosoftPreview
Allow: /Cloudflare
# Security › WAF › Custom rules › Create rule
Expression: (http.user_agent contains "MicrosoftPreview")
Action: Skip › All Super Bot Fight Mode rules
# Also check Security › Bots: "Block AI bots" can block it regardless of robots.txt.WordPress
# WordPress serves a virtual robots.txt. Edit it with your SEO plugin:
# Yoast: SEO › Tools › File editor · Rank Math: General Settings › Edit robots.txt
User-agent: MicrosoftPreview
Allow: /nginx
# nginx serves every user agent by default.
# Make sure no rule like this blocks it:
# if ($http_user_agent ~* "MicrosoftPreview") { return 403; }Apache
# Apache serves every user agent by default.
# Make sure .htaccess has no rule like this:
# RewriteCond %{HTTP_USER_AGENT} MicrosoftPreview [NC]
# RewriteRule .* - [F,L]05 · Block
How to block MicrosoftPreview
Start with robots.txt. If MicrosoftPreview keeps showing up in your logs, block it at your CDN or web server.
robots.txt
User-agent: MicrosoftPreview
Disallow: /Cloudflare
# Security › WAF › Custom rules › Create rule
Expression: (http.user_agent contains "MicrosoftPreview")
Action: BlockWordPress
# WordPress serves a virtual robots.txt. Edit it with your SEO plugin:
# Yoast: SEO › Tools › File editor · Rank Math: General Settings › Edit robots.txt
User-agent: MicrosoftPreview
Disallow: /nginx
# In your server { } block:
if ($http_user_agent ~* "MicrosoftPreview") {
return 403;
}Apache
# .htaccess
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} MicrosoftPreview [NC]
RewriteRule .* - [F,L]
</IfModule>06 · User agents
User agents we see for MicrosoftPreview
The user agent published by the operator:
Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; MicrosoftPreview/2.0; +https://aka.ms/MicrosoftPreview) Chrome/100.0.4896.127 Safari/537.3607 · Verification
Is it really MicrosoftPreview?
Anyone can copy a user agent. Real MicrosoftPreview requests come from the IP ranges published at bing.com/toolbox/bingbot.json.
FAQ
Questions about MicrosoftPreview
What is MicrosoftPreview?
It is a Microsoft user agent that fetches pages to build previews. Microsoft lists it on Bing's page about its crawlers.
Should I block MicrosoftPreview?
Usually not. Blocking it can prevent previews of your pages in Microsoft products.
How do I verify MicrosoftPreview?
Check the request IP against Microsoft's published Bingbot IP list.
Last reviewed Oct 8, 2026