📊HAR File Viewer

About this tool

Export a HAR from your browser's DevTools (Network tab → Export HAR) and open it here. You get a summary (requests, bytes transferred, total time, failures and types), a filterable table with a waterfall, and request details with timings and headers. Download a sanitised copy before sharing it.

Debugging with HAR files

A HAR (HTTP Archive) file is a JSON recording of everything a page loaded: each request's URL, method, headers, cookies, timings (DNS, connection, TLS, waiting for the server, download), status and often the response body. Support teams and developers use them to diagnose slow pages, failed requests, redirect loops, CORS errors and caching problems. The waterfall shows what loaded when, so you can spot render-blocking scripts or slow API calls, and failed requests are shown in red. Because HARs routinely contain session cookies, Authorization headers, API tokens, form submissions and personal data, they're risky to share. The file is read only in your browser here. The sanitised download replaces Cookie, Set-Cookie, Authorization and other credential headers, token-like query parameters such as token, code and key, POST bodies and response bodies with [redacted], keeping the structure needed for debugging. Honest limits: review the sanitised file before sending, because custom header or JSON field names can still carry secrets. Very large HARs (100 MB+) may be slow. The HTTP headers analyzer, HTTP status codes and the JSON formatter are related.

Frequently asked questions