Operator
Critical Css
Critical Css runs 2 bots across 2 agent types. Each one is a separate user-agent so you can allow or block them independently.
Bot
Critical CSS BotGeneric Crawler · General
Generic Crawler
General
Critical CSS Bot is operated by Critical Css. Generic programmatic data extraction with intent that varies case-by-case. Worth checking the operator before blocking, some are legitimate research, some are abusive.
Criticalcss.comDevOps & Monitoring · Monitoring
DevOps & Monitoring
Monitoring
Criticalcss.com is operated by Critical Css. Site-monitoring, uptime, performance, or QA tooling, usually run by a third-party SaaS on behalf of someone who manages the site. Rarely affects rankings or visibility.