HAR Viewer
Find a slow or failed request in a browser network recording.
Inspect a browser export
In Chrome, open Developer Tools → Network, record the activity, then use Export HAR (sanitized). In Firefox, open Network and use Save All As HAR. Upload the .har file here, or open one inside an extracted archive. Search requests, compare recorded durations and select a transaction for headers, cookies, parameters and saved bodies.
Upload, storage and sensitive data
Your file is uploaded and stored under the site's normal artifact retention and sharing rules. Parsing runs in a browser worker after upload. This is not a local-only tool. An artifact URL provides access to its contents while retained. HAR files can contain credentials, personal data and HTTPS contents. Even a sanitized browser export can contain sensitive URLs or body data; review it before sharing.
Request summaries hide URL credentials and query values. Reveal recorded details deliberately. This display masking does not anonymize the HAR or change who can download it. Recorded URLs are never requested or replayed, and embedded HTML, images and scripts are not rendered.
Supported files and limits
HAR 1.2 JSON saved as UTF-8, with or without a BOM: up to 16 MiB, 20,000 entries, 1,000 pages and 32 nesting levels. Only .har names are admitted (case-insensitive). Scroll through all requests in one continuous waterfall. Select a row to open its details in place. Header, cookie and parameter lists are limited to 512 items each. Work and string limits also apply; expensive archives can exceed a 30-second parsing deadline.
Saved response bodies can be inspected or downloaded up to 2 MiB each, with a 32 MiB download budget per opening. Text previews are bounded to 64 KiB. Missing, empty, invalid or unsupported bodies are labeled; saved text and decoded base64 are not promised to be original wire bytes. Download the unchanged HAR for data outside these limits.
Read what was recorded
Missing sizes and timings remain unknown. SSL is part of connection time. Redirects and repeated URLs remain separate requests. A HAR can contain decrypted HTTPS content saved by the browser, but omitted bodies cannot be recovered. This viewer does not record traffic, replay requests, edit archives or guarantee complete redaction.