Frequently Asked Questions
Is my video really not uploaded?
Correct. ClipSqueeze loads a WebAssembly build of FFmpeg into your browser tab and runs the compression on your own CPU. Open your browser DevTools → Network tab and you will see no request that contains your video.
What's the maximum file size?
Practical limit is about 1 GB on desktop, lower on mobile. Browsers cap memory per tab at 2–4 GB and FFmpeg needs working memory for both input and output.
Why is it slower than HandBrake?
WebAssembly FFmpeg is about 2–5× slower than native FFmpeg because the browser sandbox prevents some CPU optimizations (e.g. AVX2). For very large files, HandBrake on desktop is still faster.
Will the quality be acceptable?
ClipSqueeze uses x264 with preset 'veryfast' and a target bitrate calculated from your chosen output size and the video duration. For most social-media use the quality is good. If you need best-in-class quality, use a desktop encoder.
Which output format?
MP4 (H.264 + AAC). It plays everywhere — Email clients, Discord, WhatsApp, iOS, Android, and web.
Do you support batch processing?
Single file at a time today. Batch support coming soon.
Why does it download something from unpkg.com on first load?
That's the FFmpeg WebAssembly core (~30 MB). Your browser caches it after first load. Your video is never sent there.
Can I trust this?
Open Network tab in DevTools and watch — the only outbound request during compression is the FFmpeg core download (one time). After that, zero network activity. Your bytes never leave your device.