HAR Viewer Online
Drop a .har file from DevTools to see every request with a timing waterfall, the failed and slow ones counted, and the headers, payload, response and cookies of each. No account and no upload.
HAR Viewer & HAR File Analyzer for VS Code and Cursor, free
- Click a .har file in VS Code to see the request table with a waterfall split into DNS, connect, TLS, waiting and download.
- Save redacted copy: Authorization headers, cookies, tokens and passwords become [REDACTED], so you can send the capture to someone.
- Copy as cURL or fetch, Export filtered requests to a new HAR, and a 47 MB capture with 30,000 requests shows in under 1 second.
Optional Zovo Pro, USD 19 once: compare two HAR files, a Postman collection and CSV for Excel. 3 free tries for each.
Drop a .har file here
or
HAR 1.1 and 1.2 from Chrome, Edge, Firefox and Safari DevTools, and from proxy tools such as Charles, Fiddler and mitmproxy.
| # | Status | Method | URL | Type | Size | Time | Waterfall |
|---|
Blocked DNS Connect TLS Send Waiting Download. Click a column title to sort, click a row for its details.
Open this in VS Code or Cursor
The free HAR Viewer extension opens a .har file with a click inside VS Code and Cursor: the same table and waterfall, Copy as cURL or fetch, Export filtered requests to a new HAR, and Save redacted copy, which replaces tokens, cookies and passwords with [REDACTED] so the capture is safe to share.
Free, MIT license. About HAR Viewer for VS Code.
Zovo Pro
Compare two HAR files, Postman and CSV export. Zovo Pro, USD 19 once.
In the HAR Viewer extension, Zovo Pro compares two captures (what got slower, bigger, failed, new or gone, as a Markdown report), saves the requests as a Postman collection v2.1 with a choice to redact tokens, and saves them as CSV for Excel with every timing phase. Each Pro tool works 3 times for free. One payment covers the Pro tools in 22 Zovo extensions. Everything that is free stays free.
After a card payment you get a key on the page. With GitHub Sponsors you sign in from the extension. Details on the Zovo Pro page.
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Questions
Is my HAR file uploaded anywhere?
No. The page reads the file inside this tab. Its Content Security Policy sets connect-src to none, so the page cannot send your capture anywhere, and it loads no library. A HAR often holds cookies and tokens, so this matters: open the Network tab of your browser tools and you will see no request when a file opens.
How do I save a HAR file?
In Chrome, Edge or Firefox open DevTools, go to the Network tab, reload the page and choose Save all as HAR (the download arrow in Chrome). Safari calls it Export HAR. Then drop the file here.
What does the waterfall show?
One bar per request on a shared timeline that starts with the first request. The bar is split into blocked, DNS, connect, TLS, send, waiting and download, from the timings in the file. Click a row and the Timing tab gives the numbers.
What counts as failed or slow?
Failed means a status of 400 or more, or no response at all (cancelled or refused). Slow means the request took more than 1 second. The summary counts both, and the status list filters to them.
Does it warn about secrets?
Yes. When the capture holds Authorization or API key headers, cookie headers, or tokens in URLs or bodies, a banner says how many. The page never changes your file. The free VS Code extension writes a redacted copy with those values replaced.
Does it work offline?
Yes. After the first visit the page keeps a copy of its own files, so it opens HAR files with no connection.
What is free and what is Zovo Pro?
Everything on this page is free. In the HAR Viewer extension the table, waterfall, Copy as cURL, Export filtered and Save redacted copy are free too. Comparing two HAR files, the Postman collection and the CSV export are Zovo Pro, with 3 free tries each. One USD 19 payment covers the Pro tools in every Zovo extension.