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HAR file analyzer

HAR Analyzer — View, Redact and Diagnose HAR Files Online

Open a .har file to see every request on a waterfall, filter failing and slow calls, and download a copy with tokens and cookies removed. It runs in your browser, so session secrets never leave your device. Signed-in users also get an AI root-cause diagnosis.

Get the AI diagnosisSee plans and prices

Private HAR viewer

Parsed locally. Unlike upload-based analyzers, your Authorization headers and cookies are never sent to a server.

One-click redaction

Download a sanitized HAR without auth headers, cookies, API keys or token query parameters — safe to attach to a ticket.

AI root cause

Failing and slow calls are explained with likely causes — CORS, auth, timeouts, caching, payload size — and the fix.

What the analyzer reports

{
  "requests": 214,
  "errors": 3,
  "slow_over_1s": 5,
  "total_time": "6.8s",
  "statuses": {
    "2xx": 198,
    "3xx": 13,
    "4xx": 2,
    "5xx": 1
  },
  "redacted": [
    "Authorization",
    "Cookie",
    "Set-Cookie",
    "?access_token="
  ],
  "top_issue": "POST /api/checkout → 504 after 30,012 ms (upstream timeout)"
}

How to analyze a HAR file

  1. 01

    In Chrome, Edge or Firefox open DevTools → Network, reproduce the problem, then choose Save all as HAR.

  2. 02

    Open the .har file above — requests, errors and timings appear instantly.

  3. 03

    Filter Errors or Slow, or search by URL, to find the failing call.

  4. 04

    Download the redacted HAR to share, or sign in for the AI root-cause diagnosis.

HAR analyzer questions

What is a HAR file?
An HTTP Archive: a JSON log of every request a browser made — URLs, headers, status codes, timings and responses. Support teams ask for it to debug web problems.
Is it safe to share a HAR file?
Not as-is: it contains cookies and tokens that can log someone into your account. Use the Redacted HAR download here before sharing.
Is this a Google HAR Analyzer alternative?
Yes. It shows the same request list and timings, adds a waterfall, filters and redaction, and works offline in the browser.
How large can the HAR file be?
Up to 80 MB. Very large captures show the first 1,500 rows in the table; the summary covers all requests.
What does the AI diagnosis cost?
The viewer and redaction are free. AI diagnoses are included for signed-in users with a daily allowance; only failing and slow requests without secrets are sent.

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