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Calibre

paid From $75/mo · Founded 2017 · cloud

Site performance monitor with Lighthouse-based scoring + slack alerts.

What it does well

  • Automates Google Lighthouse tests for consistent performance tracking over time.
  • Integrates with Slack and GitHub to provide alerts within existing developer workflows.
  • Allows setting performance budgets to prevent regressions on key metrics.

Where it falls short

  • No free tier is available for small projects or individual evaluation.
  • The $75/month starting price can be high for freelancers or small teams.
  • Focuses solely on front-end performance, requiring other tools for uptime or backend monitoring.
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Tags: performancecore-web-vitalssmall-team

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