Upload a HAR file or paste JSON content to visualize HTTP request waterfalls, response headers, and performance metrics. Pure client-side processing, no data upload.
Drag & drop HAR file here, or click to select
Supports .har files up to 50MB
The HAR File Viewer is an online tool designed for web developers and DevOps engineers. By parsing HTTP Archive (HAR) files, you can visually inspect all HTTP interactions between the browser and server, including request waterfalls, response time analysis, resource loading statistics, and other key performance metrics.
HAR (HTTP Archive) is a JSON format file that records HTTP interactions between a browser and server. It contains request URLs, methods, headers, response status codes, response headers, body sizes, timestamps, and more — essential for web performance analysis and troubleshooting.
In Chrome: 1) Open DevTools (F12); 2) Go to the Network tab; 3) Perform the actions you want to record; 4) Right-click the request list and select "Save all as HAR with content". Firefox and Edge support similar operations.
Yes, HAR files may contain cookies, Authorization headers, POST request bodies, and other sensitive data. This tool processes everything locally in your browser — no data is uploaded to any server. Always review and remove sensitive info before sharing HAR files.
This tool supports HAR files up to 50MB. For files with many requests, use the filter feature to narrow by domain or type for a better browsing experience.
The waterfall chart shows each request's phase timings: DNS lookup (purple), TCP connect (orange), SSL handshake (green), request sending (dark blue), waiting for response (light blue), content download (gray). Analyzing these phases helps identify performance bottlenecks.