HAR Analyzer

What is a HAR file?

A HAR (HTTP Archive) is a JSON recording of browser network activity: request URLs and methods, response status and headers, recorded sizes, and available timing phases. Its fields are optional, so the analyzer marks missing data as unavailable instead of inferring it.

How do you analyze a HAR file?

Start with failed status codes and the slowest requests, then compare the waterfall phases. Select a request to inspect its URL, headers, recorded size, and available timings. SymptomInspectNext check 4xx or 5xx responseStatus, URL, request and response headersConfirm the requested endpoint and review recorded headers for failure context.

How private is a HAR file?

HAR files can contain cookies, authorization headers, query secrets, and request or response bodies. The analyzer processes the selected file in this tab and does not upload its contents; page analytics are separate from HAR processing and do not receive the file.

What can a HAR leave out?

Browsers and exporters may omit timings, headers, body text, or size fields. Recorded size uses the best available transfer, body, or content-size field and may differ from bytes transferred. Missing or negative timing phases are omitted from the waterfall; unavailable values remain clearly labeled. HAR AnalyzerTiming and size detail depends on what the browser recorded.