I built an API monitoring tool because every existing one either costs too much or restricts commercial use

The problem I was building a side project and needed to monitor a few API endpoints. I tried the usual suspects: UptimeRobot free : 50 monitors, sounds great — until you read "non-commercial use only" Better Uptime : $20/mo minimum for anything useful Pingdom : No free tier at all Datadog : Powerful, but $100+/mo overkill All of them also share another problem: they only check status codes . Your API can return 200 OK with a body of {"error": "database connection failed"} and most uptime tools will happily mark it as "up." What I built CheckAPI ( https://checkapi.io ) — API health monitoring with a focus on what actually matters to developers. Key features 1. Response body keyword validation Set a keyword that must be present (or absent) in the response body. Example: check that "status":"ok" exists in the response — not just that the server responded. 2. SSL certificate expiry alerts Get notified 14 days before your cert expires. Especially useful if you're using Let's Encrypt's 90-da