Sift — HTTP capture viewer — Jackson F. de A. Mafra

Sift is a read-only viewer for HTTP session captures. You drag a capture file onto the panel and Sift renders a navigable request and response inspector. It parses the file entirely in memory and never writes anything to disk.
It opens three formats:
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HAR (.har), the HTTP Archive JSON format exported by browser developer tools and many HTTP clients.
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Fiddler SAZ (.saz) session archives.
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Charles session exports, both .xml and .trace.
All three are normalized into the same internal model, so the inspector behaves identically regardless of where the capture came from.
What it does:
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Shows a request list with method, status (colored by class), host, path, response type, size, and duration. The list is virtualized, so captures with thousands of requests stay responsive.
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Shows a detail pane with tabs for request and response headers, query parameters, cookies, request body, response body, and timing.
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Pretty-prints and syntax-highlights JSON, XML, HTML, CSS, and JavaScript bodies. Large bodies are held behind an explicit "render anyway" control so a single request cannot lock up the panel.
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Masks sensitive values by default. Authorization headers, cookies, Set-Cookie headers, common API-key headers, and token-shaped query parameters are hidden until you click to reveal an individual value, or use the global reveal toggle.
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Decompresses gzip and deflate response bodies and reassembles chunked transfer encoding. Brotli-encoded bodies cannot be decoded with the bundled library and are shown as raw bytes with a clear "not decoded" badge rather than failing.
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Exports a sanitized HAR. This rebuilds a valid HAR file with every sensitive value replaced by a placeholder, so a capture can be shared without leaking credentials. The export is the only file Sift produces, and only as a download you start.
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Searches across URL, headers, and body text, with quick filters by method, status class, host, and response MIME type.
Who it is for: developers and QA engineers who need to read a capture someone sent them, or one they exported, without uploading it to an online tool or installing a heavier proxy. Because nothing is persisted, the panel is empty again after a reload, by design.
How to use it: open Chrome DevTools, select the "Sift" panel, and drop a capture file onto it. There is no toolbar popup; the extension exists only as a DevTools panel.
Limitations, stated plainly:
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Brotli (br) response bodies are not decoded.
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Encrypted or password-protected SAZ archives are detected and refused with a clear message rather than guessed at.
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The Charles .chls and .tcpsf formats and packet captures (pcap/pcapng) are not supported. Export HAR from those tools instead.
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There is no live capture in this version. Sift views files you already have.