Compare two HARs with HAR Desk
This opens two captures of the same made-up checkout, one before and one after a change. The counts show at once; the full list of added, removed and changed requests, with the status and timing differences, is part of Pro.
- Load the first capture (A) on the Inspect tab, then open Compare and choose the second (B).
- Read the counts: requests added in B, removed from B, changed and unchanged.
- With Pro, open the list to see each changed request with its status, size and time difference.
- Download the comparison as Markdown to paste into a ticket or pull request.
What to know
Two captures of the same flow rarely line up one to one. Requests are matched by method and a normalised URL: the host and path with numeric ids, UUIDs and long hex segments written as :id, and only the names of the query parameters, so a changing timestamp or cache-buster does not split one request into two. Repeated identical requests are matched in order.
A matched pair counts as changed when the status differs, when the time differs by at least 200 ms and by a factor of 1.5, when the size differs by at least 2 KB and a factor of 1.25, or when the content type differs. Small wobble in timing is the normal state of a network, so smaller differences are not reported.
Compare is useful for a regression after a deploy, a flow that works on one network and not another, or a capture from a user against one of your own. If you plan to share the result, compare sanitized files, because the comparison shows URLs and status codes as they are in the files you load.
Updated · Cosmovex
Questions
How are requests matched between the two files?
By method plus host and path, with id-like segments written as :id and only query parameter names kept. The nth occurrence in A is matched to the nth in B.
What counts as a change?
A different status code, a time difference of at least 200 ms and 1.5x, a size difference of at least 2 KB and 1.25x, or a different content type. Smaller differences are treated as the same.
What is free and what is Pro?
Loading both files and the counts are free. The detailed list of added, removed and changed requests and the Markdown export need Pro, which is a one-time $29.
Are the files uploaded?
No. Both are read and compared in your browser tab.
The free plan covers everything on this page. HAR Desk Pro ($29, paid once) is described on the HAR Desk page.
