HAR file viewer and analyzer

A HAR file is a JSON log of the requests a page made in the browser: each address, method, status, the headers, the bodies and how long it took. Browsers save it from devtools, so it is the usual way to send a network problem to someone else.

In Chrome or Edge, open devtools, go to the Network panel, do what goes wrong, then click the download arrow to export the HAR. In Firefox, right-click any request in the Network panel and choose Save All As HAR. In Safari, use the Export button in Web Inspector’s Network tab.

Drop it on this page, or choose it with the button above, and it opens in your browser with nothing uploaded. You can also drag a .har file into the Network panel of Chrome or Edge devtools, or use Import HAR File in the Network panel settings in Firefox. A HAR file is plain JSON, so any text editor opens it too, but a single page load can run to thousands of lines.

Each entry is one request: the method and address, the status, how long it took, the request and response headers and the bodies. Start with the failures (4xx and 5xx statuses and requests that never got an answer), which this viewer lists first. Then read the response body of the first failure for the error message, and compare request headers such as cookies and authorization when a call fails for one person but not another. Look at the timeline for requests that stall.

No. The viewer reads the file in your browser with JavaScript. Nothing is sent to Faylee or anyone else, and nothing is kept once you close the tab.

Often not as it is. A HAR file can hold cookies, authorization headers, tokens and whatever was typed into forms, and a copied cURL command carries them too. Check it before you send it, or import it into Faylee, which hides secrets before saving it as a link.

Browsers leave out bodies they did not keep, such as for requests made before devtools was open, and some exports drop them on purpose. The viewer also skips bodies saved as base64, like images and fonts, since there is nothing to read in them.

A HAR file only has the network. Faylee records the screen, the console, the clicks and every request on one timeline, hides secrets in the browser, and shares it all as a link your team or coding agent can open. You can also import a HAR file into Faylee from the recordings page.