Does this video compressor upload my video?

No. Your video is processed entirely inside your browser using WebAssembly technology (FFmpeg.wasm). Nothing is ever sent to any server. Your files never leave your device.

What video formats are supported?

The compressor supports MP4, MOV, WebM, and AVI files. Output is delivered as MP4 for maximum compatibility.

How does browser-based video compression work?

The tool uses FFmpeg compiled to WebAssembly, which runs the full FFmpeg video processing engine natively in your browser without any server involvement.

Is there a file size limit?

There is no hard limit imposed by SwissTools. However, your browser and device memory may limit very large files (e.g. above 2GB). For most use cases up to 500MB works smoothly.

Free Video Compressor – No Upload, 100% Private

Drop your video here

or click to browse your files

MP4 · MOV · WebM · AVI — up to ~2 GB

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Quality (CRF) Medium

Resolution

Speed preset

Audio

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Your video never leaves your device. Compression runs entirely in your browser using WebAssembly. SwissTools has zero access to your files.

COMPRESSING…

Processing locally in your browser. Do not close this tab.

✓

Compression complete

Your file is ready to download.

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Original size

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Compressed size

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Space saved

⬇ Download Compressed Video

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Keep SwissTools free

This tool will always be free, with no account required. If it saved you time, a small donation helps keep the servers running.

Support on Ko-Fi

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Why use a browser-based video compressor?

Traditional online video compressors require you to upload your video to a remote server — which raises serious privacy concerns, especially for personal footage, screen recordings of sensitive work, or any video containing private information. With SwissTools Video Compressor, your video never leaves your device. Compression is handled entirely by FFmpeg compiled to WebAssembly, running natively inside your browser.

There's no account to create, no file size quota to hit, and no waiting in a server queue. Since everything runs locally, compression speed depends only on your own device.

Frequently Asked Questions

No. Your video is processed entirely inside your browser using WebAssembly (FFmpeg.wasm). Nothing is sent to any server — your file never leaves your device. SwissTools cannot see or access your videos.

The compressor accepts MP4, MOV, WebM, and AVI files. The compressed output is delivered as an MP4 file for maximum cross-device compatibility.

SwissTools imposes no hard file size limit. In practice, your browser and available device memory determine the upper boundary — most files up to 500 MB work smoothly. Very large files (1–2 GB) may work on devices with sufficient RAM.

The tool uses FFmpeg compiled to WebAssembly — a binary format that runs at near-native speed inside the browser. When you compress a video, FFmpeg re-encodes it using the H.264 codec with the settings you choose, outputting a smaller MP4 file.

CRF (Constant Rate Factor) controls the quality-to-size tradeoff. Lower values (18–23) produce higher quality but larger files. Higher values (28–35) produce smaller files at the cost of some quality. A value of 23–28 is a good balanced choice for most use cases.

Yes, completely free with no account required. SwissTools is supported by optional donations and non-intrusive ads. If this tool helps you, consider buying us a coffee on Ko-Fi.

Compress videos.
Nothing leaves your device.

Keep SwissTools free

Why use a browser-based video compressor?

Frequently Asked Questions

More privacy-first tools

Compress videos.Nothing leaves your device.

Keep SwissTools free

Why use a browser-based video compressor?

Frequently Asked Questions

More privacy-first tools

Compress videos.
Nothing leaves your device.