About JustCompressVideo

JustCompressVideo is a free, browser-based video compression tool. Drop in a video, choose your quality settings, and get a smaller file — no upload, no account, no cost.

How it works

This tool uses ffmpeg.wasm, a WebAssembly port of the industry-standard FFmpeg library. When you select a video file, it is loaded directly into your browser's memory. All H.264 encoding happens locally using your device's CPU — nothing is sent to any server.

Why we built it

Most online video compressors either upload your files to cloud servers (raising privacy concerns), add watermarks to the output, or require a paid subscription for reasonable quality. We believed there was a better way: run the entire encoding pipeline in the browser, where server costs are zero, privacy is guaranteed by architecture, and watermarks are unnecessary.

Privacy

Your video files never leave your device. This is not a policy — it is an architectural fact. There is no server to receive your files. You can verify this by opening your browser's developer tools (F12), going to the Network tab, and watching for any outbound requests when you compress a video. You'll see none containing your video data.

The site uses Google Analytics (with your consent via the cookie banner) to understand aggregate usage patterns. No video content, filenames, or processing results are tracked.

Technical details

• Powered by ffmpeg.wasm 0.12 (single-threaded mode)
• H.264 encoding via libx264 with CRF quality control
• Output: MP4 container (H.264 video + AAC audio)
• Quality range: CRF 18 (100% quality) to CRF 51 (5% quality)
• Resolution options: Original, 1080p, 720p, 480p, 360p
• Output filename: {originalName}_compressed.mp4

Part of a family of tools

JustCompressVideo is part of a family of free browser-based video tools. If you need to trim a video instead of compressing it, try JustTrimVideo.

Contact

Questions or feedback? You can reach us through the contact information on our privacy policy page.