Free Monitoring Tools
Developer tools for uptime monitoring, security analysis, and infrastructure debugging. No signup required.
Uptime Calculator
Calculate exactly how much downtime your SLA allows. Convert uptime percentages to minutes per day, hours per month, and days per year.
HTTP Header Checker
Analyze HTTP response headers, security configuration, redirect chains, and server behavior for any URL.
SSL Certificate Checker
Verify SSL/TLS certificate validity, expiry date, issuer, and protocol. Catch expiring certificates before they cause outages.
JWT Decoder
Decode JSON Web Tokens in your browser. Inspect header, payload, claims. Nothing sent to our server.
CORS Checker
Test CORS config of any API. Runs preflight OPTIONS + actual request, shows Access-Control-* headers.
Go Beyond One-Time Checks
These tools give you a snapshot. PulseAPI gives you continuous monitoring — checking your endpoints every 10 seconds, alerting on downtime, SSL expiry, and slow responses. Free to start.