Inspect HTTP Archive (.har) files in your browser. Visualizes request waterfall timings, payload sizes, MIME types, and response status codes with zero network uploads, keeping session cookies and auth tokens private.
Runs entirely in your browser
A HAR file (HTTP Archive) is a JSON export of everything a browser’s network panel recorded during a session — every request and response, with timings, sizes, headers and status codes. Support teams and developers often ask for one to diagnose a slow page or a failing request, but HAR files are awkward to read raw. This viewer parses a .har file and presents it clearly: a request waterfall showing how long each step took, payload sizes, MIME types, and the HTTP status of every response.
That view makes performance and error problems visible at a glance. A long bar in the waterfall pinpoints what is slowing a page; a cluster of red statuses shows which requests failed; oversized payloads reveal what is bloating a load. It turns an opaque log into an actionable picture.
Importantly, the file is parsed entirely in your browser and nothing is uploaded. This is more than a convenience: HAR files frequently contain session cookies, authentication tokens and other sensitive request data, so analysing one locally keeps those secrets on your machine rather than sending them to a third-party service.
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