🌐 Request Configuration
🔒Requests sent directly from browser. Timing calculated locally via Performance API.
Pure Frontend · TTFB Measurement · Phase Timing Analysis · Multi-Request Comparison
Zero Dependencies · Works OfflineThe HTTP Request Timer is a pure frontend online tool for precisely measuring the timing of each phase of an HTTP request. Enter a target URL, and the tool sends a request while using the browser's Performance API to record DNS lookup, TCP connection, TLS handshake, request sending, waiting for response (TTFB), content download, and other phase timings. Results are displayed as visual timing bars and detailed data. Supports GET/POST/PUT/DELETE/HEAD methods with custom headers and request body, plus multi-request history comparison. All timing is calculated locally in the browser.
Step 1: Select an HTTP method and enter the target URL.
Step 2: Add custom headers or request body in JSON format if needed.
Step 3: Click "Send Request" or use Ctrl+Enter, then wait for the request to complete.
Step 4: Review the timing bars and data for each phase. Click "Copy JSON" to export results.
Developers measure API endpoint TTFB and total time to determine if slow requests are due to DNS resolution, network latency, or server processing.
Compare request phase timings with and without CDN to verify acceleration effectiveness.
Make multiple requests to the same URL and compare network latency changes across different time periods.
Measure TTFB of critical resource loads to optimize API request performance for first-screen rendering.
TTFB (Time To First Byte) is the time from sending a request to receiving the first response byte, including DNS+TCP+TLS+server processing time. The browser Performance Resource Timing API provides detailed request phase data: domainLookupStart/End for DNS, connectStart/End for TCP, secureConnectionStart/End for TLS, requestStart to responseStart for TTFB, and responseStart to responseEnd for download. Optimizing TTFB typically requires server-side improvements (caching, CDN, database query optimization).
Measures DNS lookup, TCP connection, TLS handshake, request sending, waiting for response (TTFB), content download, and total time.
Browsers cache DNS and TCP connections. Repeated requests to the same domain may show 0ms for DNS and TCP phases. Clear cache for first-time measurements.
Yes, GET, POST, PUT, DELETE, and HEAD methods are supported with custom headers and request body.
Browser CORS policy restricts cross-origin requests. Test CORS-enabled APIs or use browser extensions to temporarily disable CORS for development.
No. Requests are sent directly from the browser to the target URL. Timing data is calculated locally by the Performance API.
Yes. Copy results as JSON or download as a file for record-keeping and comparison analysis.