velprove

Velprove monitors whether your web application works — not just whether your server responds. Traditional uptime tools check for a 200 status code. Velprove launches a real headless browser to verify login pages accept credentials, chains multi-step API requests to test full authentication flows, and validates response content to catch endpoints returning incorrect data. Four check types available on every plan including free: HTTP/Ping for standard uptime, API Validation for JSON path and header assertions, Multi-Step API to chain sequential requests with variable passing, and Browser Login checks with failure screenshots.

Free plan includes 10 monitors, 1 browser login check, multi-step API checks, and email alerts. Commercial use allowed. Starter plan adds Slack and webhook alerts with 1-minute intervals. Pro plan adds PagerDuty, 30-second intervals, and 10 browser checks.