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🎬

Video Compressor

Compress videos in your browser — no upload to servers. Fast, private, and free.

🎬

Drop a video here or click to browse

Supports MP4, WebM, MOV, AVI

Compress video files without losing quality

The Video Compressor shrinks the file size of your videos so they are easier to email, upload, message, or store, all while keeping them watchable. It re-encodes your clip using the widely supported H.264 codec inside an MP4 container, which plays on virtually every phone, browser, and media player. Whether you are trimming down a screen recording before sending it to a colleague, fitting a clip under a messaging app's attachment limit, or saving space on a full phone, this tool gives you control over the trade-off between size and quality.

Everything happens locally in your browser using FFmpeg compiled to WebAssembly. Your video is never uploaded to a server; it is read directly from your device and processed on your own machine. That means your files stay private, and the tool works even after the page has loaded if your connection drops. The first compression of a session downloads the FFmpeg engine from a public CDN, which can take a few seconds, after which conversions run entirely offline.

How to compress a video

Drag a video onto the upload area or click to browse and select a file (MP4, WebM, MOV, and AVI are supported). Use the Compression Quality slider to choose your priority: higher percentages keep more detail and produce a larger file, while lower percentages shrink the file aggressively. The label updates between High Quality, Balanced, and Small File so you know roughly what to expect.

Next, pick a target resolution. Leaving it at Original keeps the frame size, while choosing 720p or 480p downscales the video, which both reduces the file size and speeds up encoding considerably. When you are happy with the settings, click Compress Video and watch the progress bar. When it finishes you will see the original size next to the new size, the amount saved, and a button to download the compressed MP4.

Tips for the best results

Lowering the resolution is often the single biggest lever for both file size and speed, so if your video does not need to be full HD, try 720p first. The encoder uses an ultrafast preset to keep processing time reasonable in the browser, so very long or high-resolution clips will still take time and memory; if a large file struggles, compress a shorter section or pick a smaller resolution. Because the output is standard MP4 with the moov atom moved to the front for fast start, it begins playing quickly when streamed online.

Frequently Asked Questions

Are my videos uploaded to a server?▼
No. Compression runs entirely in your browser using FFmpeg compiled to WebAssembly, so your video never leaves your device. Only the FFmpeg engine itself is fetched once from a public CDN.
What video formats can I compress?▼
You can upload MP4, WebM, MOV, and AVI files. The compressed output is always an MP4 file using the H.264 video codec and AAC audio for broad compatibility.
How much smaller will my video be?▼
It depends on the quality and resolution you choose and how the original was encoded. The result screen shows the exact size saved; lowering the resolution and the quality slider together produces the smallest files.
Why does the first compression take longer to start?▼
The first time you compress in a session, the tool downloads the FFmpeg engine from a CDN. After that it is cached, so subsequent compressions begin almost immediately.
Is there a file size limit?▼
There is no hard limit set by the tool, but processing happens in your browser's memory, so very large or long videos may be slow or fail on low-memory devices. Reducing the resolution helps a lot.
Is the Video Compressor free?▼
Yes, it is completely free to use with no sign-up, watermark, or account required.

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