Fit a recording into a chat or email by trading resolution and bitrate — with the tradeoff stated, not hidden.
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Select a video; its resolution, duration, and size are shown.
Choose MP4 (H.264/AAC) or WebM (VP9/VP8), then pick a preset or custom resolution and bitrate.
Export — the video replays through a scaled local canvas and re-encodes at the chosen bitrate and supported browser codec.
Before/after sizes are reported from the actual output bytes.
The selected MP4 or WebM container signature is checked, then the compressed output is re-decoded locally to confirm it plays. Its true byte size and duration are measured before download.
Size ≈ bitrate × duration. A one-minute clip at 1 Mbps video + 96 kbps audio is roughly 8 MB. The tool estimates this before you export and reports the real size after.
Yes when your browser and operating system expose an H.264/AAC MP4 encoder. The tool verifies a real MP4 container before enabling download. If MP4 is unavailable, WebM remains selectable; renaming a WebM file to .mp4 is never used.
No. The file is opened with your browser's File API and processed by code running in your tab. You can confirm this yourself: open your browser's developer tools, watch the Network panel, and process a file — no request carries your file's bytes. See our How it works page for a step-by-step verification guide.
The same local tool, preconfigured for a specific job.
Technical guidance, limitations, and safer workflows related to this tool.
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Set in/out points on a preview player and export the range as a locally re-encoded WebM clip.
Re-encode a video with the audio track entirely absent from the output file.
Quality slider and target-size search with side-by-side comparison. Metadata is stripped by default.