← All website monitoring tools
Open-Source (16 options, 2026)
Self-hosted, code-on-GitHub options. Run on your own server, customize freely, never pay per-site fees.
Self-hosted open-source uptime monitor with status pages — Docker one-liner deploy.
Cron-job heartbeat monitoring — open-source with hosted free tier and self-host option.
Google's open-source Lighthouse audits in CI — track Core Web Vitals on every deploy.
Self-hosted uptime + status page combo — Go binary, sqlite/postgres, lightweight.
Developer-focused open-source health dashboard — YAML-driven, zero-cost self-host.
Open-source PHP status page — original Statuspage alternative, used by GitLab.
Uptime monitor that runs as GitHub Actions — entirely free, status page on GitHub Pages.
Classic Unix process + service monitor — runs locally, restarts services if they die.
20-year-old infrastructure monitoring — Core is free, XI is paid enterprise.
Enterprise-grade open-source monitoring — free forever, paid support available.
CNCF metrics + alerting standard — Blackbox exporter does HTTP/TCP/ICMP probes.
Time-series storage for metrics — old-school but reliable, paired with Grafana for dashboards.
Nagios-fork modernized — popular in European DevOps, Raw is free.
Modern Nagios fork — open source, plugin-compatible with Nagios checks.
Kubernetes-native alerting — open-source core, hosted UI for teams.
Heartbeat + Synthetics in Elastic Stack — free if self-hosted, paid Elastic Cloud.
Tips for open-source tools
- Don't run on the same server you're trying to monitor.
- Consider time-cost: free in dollars, not free in maintenance hours.
- Open-source = no vendor lock-in, but you handle backups and updates.