Compress a Video
Reduce video file size while keeping quality. Processed locally in your browser.
Drop your file here
Related tools
Compress videos in your browser, locally
Most online video compressors bottleneck on upload speed: a 200 MB clip takes longer to send than to actually compress. Filzy avoids the round trip by running ffmpeg.wasm directly in your browser. The compression uses libx264 with a CRF (Constant Rate Factor) you control, the result lands in your downloads folder, and the source file never leaves your device. Compression is GPU-free but parallelised across your CPU cores. Expect 3 to 8x size reduction on smartphone-recorded MP4 (which is usually over-bitrated for the resolution).
Files stay on your device
ffmpeg.wasm runs as a WebAssembly module inside a Web Worker. The video never reaches a server, neither for upload nor for processing.
Three quality presets
Best (CRF 18, near-archive quality), Balanced (CRF 28, good for sharing), Smallest (CRF 36, maximum compression). All use libx264, the same codec YouTube and Netflix encode in.
Native CPU speed
WebAssembly delivers near-native performance. A 5-minute 1080p clip typically compresses in 1 to 3 minutes on a modern laptop.
How to compress a video with Filzy
- 1
Drop your video
Drag the MP4, MOV or WebM file in, or click to select it. Files up to a few gigabytes work, the practical limit is your device memory.
- 2
Pick a quality preset
Best for archive, Balanced for sharing on social media, Smallest for email or chat where every megabyte counts.
- 3
Filzy encodes locally
ffmpeg.wasm decodes, re-encodes with libx264 at the chosen CRF, and writes a new MP4. Progress is shown frame by frame.
- 4
Download the compressed clip
Save it, or send it straight to another Filzy tool, like Trim, Crop or Add Watermark. Files chained between tools also stay local.