Assertwise Lab / API response time
API response timeAPI response time check: DNS, TLS, TTFB and p95
Send up to 10 sequential GET requests to an endpoint and see exactly how long each phase takes.
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How to read the result
High DNS or TLS times point to resolver or certificate-chain issues; a high TTFB with fast connect means the server itself is slow. The first request is often slower (cold connection, cache). Each request opens a new connection, so this is the worst case without keep-alive.
What this is not
Ten requests from one location are a spot check, not a performance test. Real latency budgets need load from realistic regions and traffic mixes – that is what a k6 load test is for.
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