API response time tester
Browser-side fetch latency, not server-side. Measures fetch() completion time from your browser (DNS + TCP + TLS + request + response). Includes your network conditions and the browser's connection-pool reuse, so it's not a substitute for an authoritative server-side benchmark. CORS-blocked URLs may fail entirely.
About this tool
API response time tester is a single-purpose utility on instant.tw, a free toolbox of calculators, converters, generators, and quick lookups. Everything works in your browser — nothing is uploaded, nothing is stored on a server unless explicitly noted.
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