HAR Analyzer
Free, no signup. Drop in a browser network capture to inspect failures, redirects, transfer weight, timings, caching, third parties, and tag evidence. The raw HAR never leaves this tab.
Local cap: 50 MiB and 5,000 entries. Request/response bodies, cookies, sensitive header values, and query values are never included in the report.
Runs entirely in your browser — nothing you paste is uploaded or stored. The HAR and its analyzed contents are not uploaded. Close the tab to discard the imported capture. Anonymous run-level outcome counters may be used for aggregate research; URLs, domains, IPs, and identifiers are never included, and no statistic is released below 100 runs.
How to use it
- Export a HAR with content from your browser’s Network panel.
- Select the file and analyze it locally.
- Review failed requests, redirects, third parties, resource weight, cache evidence, and detected tag requests.
- Download the sanitized JSON report when you need to share evidence. Never share the original HAR without reviewing it separately.
Site passport Local context for this saved site
Local data
Saved targets, named lists, and recent check summaries remain only in this browser.
Requests by resource type
Third-party domains
Tag and consent vendor evidence
Requests needing review
| # | Status | Type | Host / URL | Transfer | Duration | Cache |
|---|
Rate this tool
Sample report
A typical report groups requests by resource type, lists third-party hosts, and surfaces failed requests, redirectsA redirect sends browsers and crawlers from a requested URL to a different one. An HTTP redirect specifically is a 3xx status code paired with a Location header; meta refresh and JavaScript redirects achieve a similar navigation without being a 3xx response themselves. Permanent redirects (301/308) are Google's signal the target should be canonical; temporary ones (302/303/307) aren't., and explicit cache missesCaching stores a copy of a page or resource — in a browser, a CDN edge node, or a search crawler's own cache — so it can be served again without regenerating or re-downloading it. It isn't a direct ranking factor, but it feeds page speed and crawl efficiency. for review. The values always come from the selected HAR; this sample description is not a benchmark.
How it works
The browser reads the HAR locally, validates its shape and limits, removes sensitive URL and header values, then classifies the bounded request entries. No request or response bodies are included in the displayed or exported report.
What the report can show
- Failed requests and redirect responses.
- Transfer bytes and summed request duration as HAR-recorded evidence, not a page-load score.
- First-party versus third-party hosts based on the first valid request host.
- Cache hit, miss, and revalidation evidence from recorded response status and headers.
- Tag-manager, analytics, advertising, and consent loader/request patterns.
Privacy and interpretation boundaries
HAR files are sensitive source material. Analysis is local, but the original file remains your responsibility. The sanitized export contains redacted URLs and header names only—not header values, bodies, post data, or cookies. Timings can overlap, browser HAR exporters differ, and a network request does not prove a vendor processed it.
Frequently asked questions
Is my HAR uploaded?
No. The selected file is parsed and analyzed by JavaScript in this browser tab. The analyzer does not send or persist the raw HAR or its contents.
Can HAR files contain secrets?
Yes. HAR files can contain cookies, authorization headers, query values, and request bodies. This tool omits bodies, cookies, sensitive headers, and all query values from its results and exports, but you should still protect the original file.
What are the analysis limits?
Files are capped at 50 MiB and analysis at 5,000 entries. If more entries exist, the report clearly states how many were not checked.
Does tag evidence prove tracking fired?
No. A matched request or loader is evidence only. It does not prove data was accepted, attributed, or sent with valid consent.
Feature requests for Har Analyzer
Upvote what you want most. New ideas can be submitted from the floating Feedback menu; requests appear here once approved, and the most-wanted rise to the top.
You won't be emailed about that request anymore.
Loading…
➕ Request a feature
New requests are reviewed before they appear here.
Common issues & how to fix them
- Errors One or more requests failed Fix: Reproduce each intended failed request, then repair its URL, availability, or server response so the required resource returns an appropriate success status.
- Warnings One or more requests returned a redirect Fix: For unnecessary redirects, update the initiating page or request to use the final URL directly; preserve redirects that are intentional and correctly targeted.
- Information One or more responses contain explicit cache-miss evidence Fix: Confirm each miss is expected for private or uncacheable content; otherwise correct the response or edge-cache policy and verify a later request records a hit.