HAR Analyzer
HAR Analyzer is an online HAR file viewer for inspecting network requests, status codes, recorded sizes, headers, and timing phases. Open a .har or .json file to find slow requests, failed responses, and waterfall bottlenecks.
Drop a HAR file here
or choose a .har or .json file
The analyzer processes your selected HAR in this browser tab; it does not upload the file.Need a HAR file? See how to export one.
Requests
| Start | Method | Status | Domain / path | Type | Recorded size | Duration |
|---|
No requests match these filters.
Timing waterfall
QueuedDNSConnectSSLSendWaitReceive
Bars share the full capture timeline. Missing or negative HAR timing phases are omitted.
Slowest visible requests
Request breakdown
Status
Content type
Domain
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 export a HAR file?
- Open your browser’s developer tools and select Network.
- Clear the log, keep recording enabled, and reproduce the problem.
- Use Export HAR or Save all as HAR, then open the saved file here.
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.
| Symptom | Inspect | Next check |
|---|---|---|
| 4xx or 5xx response | Status, URL, request and response headers | Confirm the requested endpoint and review recorded headers for failure context. |
| Long Wait phase | Wait timing and total duration | Investigate server response time or upstream work before the first byte. |
| Large or slow transfer | Recorded size and Receive timing | Review response size, compression, and the delivery path. |
| Long DNS, Connect, or SSL phase | Connection timing segments | Check name resolution, connection reuse, network path, and TLS setup. |
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.
The redacted download removes common authentication and cookie headers, cookies, sensitive-name query parameters, URL credentials, request bodies, and response body text. It cannot identify every custom secret, so review the downloaded copy before sharing.
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.