HTTP Header Analyzer
Inspect security headers, CORS and caching directives.
RUNS LOCALLY
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API & Network
A fast, free, privacy-focused collection of essential developer utilities.
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Explore the toolbox 37
CORS Debugger
Simulate origin, method and header compatibility.
RUNS LOCALLY
HTTP Request to cURL
Turn a raw HTTP request into a safely quoted POSIX shell command.
RUNS LOCALLY
IPv4 Subnet Calculator
Calculate network, broadcast, masks and usable address ranges.
RUNS LOCALLY
SSL Certificate Inspector
Inspect an HTTPS server certificate and its presented chain.
SERVER DIAGNOSTIC