User-agent Exclusions

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FastPixel lets you stop optimizing pages for specific visitors based on their user agent, the identifier that every browser, bot, or app sends with each request. When a visitor’s user agent matches one of your exclusions, FastPixel will:

not trigger page optimization (the page isn’t added to the optimization queue)
not serve them a cached page, they receive the standard, unoptimized page instead.

Bots, crawlers, and monitoring services don’t benefit from optimization, so excluding them keeps them from consuming your pageviews usage.

How matching works #

Add one user agent per line.
Matching is case-insensitive — claude, Claude, and CLAUDE all behave the same.
Matching is a “contains” check — FastPixel looks for your text anywhere inside the visitor’s full user-agent string, so you only need a distinctive part of it, not the whole thing.
The * character can be used as a wildcard for more advanced patterns.

Example: a visitor whose user agent is Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) … Safari/537.36, ClaudeBot/1.2 is excluded if you simply add Claude, because that word appears in the string.

User agents excluded by default #

FastPixel already excludes a set of common bots, scrapers, and monitoring services out of
the box. You don’t need to add these, they’re always active, even though they don’t
appear within the plugin:

Search engine crawlers
Googlebot, Bingbot, msnbot, Slurp, DuckDuckBot, Baiduspider, YandexBot, Sogou, Exabot, Applebot, PetalBot, SeznamBot, Qwantify, MojeekBot

AI crawlers & assistants
GPTBot, ChatGPT, OAI-SearchBot, ClaudeBot, Claude-Web, anthropic-ai, PerplexityBot, Perplexity-User, CCBot, GoogleOther, Amazonbot, Bytespider, Meta-ExternalAgent, FacebookBot, Diffbot, ImagesiftBot, Omgilibot, YouBot, cohere-ai, DuckAssistBot, AI2Bot, Timpibot, PanguBot

SEO & backlink crawlers
AhrefsBot, SemrushBot, MJ12bot, DotBot, BLEXBot, rogerbot

Social & link-preview scrapers
facebookexternalhit, Facebot, Twitterbot, LinkedInBot, Pinterest, Slackbot, TelegramBot, WhatsApp, Discordbot

Uptime & availability monitors
UptimeRobot, StatusCake, Site24x7

The User-agent Exclusions field is only for the entries you add. Your additions are
combined with the built-in list above.

Tips #

Be specific. Because matching is a “contains” check, a short word can match more than
you expect (for example, bot would match many user agents). Use a distinctive token, and
add surrounding characters like Claude/ — if you need to narrow it down.
Use * for patterns. For example, *PreviewBot* matches any user agent containing
“PreviewBot”.

Performance-testing tools are never excluded #

Tools that measure your site’s speed are always served the cached, optimized page, so
your scores reflect the optimized version and cannot be excluded, even if you add a
matching entry. This protection covers Google PageSpeed Insights / Lighthouse, GTmetrix,
Pingdom, and WebPageTest.