How much smaller will my video get?

It depends on the source. Videos exported from phones or editors are often over-encoded, so Balanced typically saves 40-70%. The Smallest preset also scales the video down to 1280px wide for the biggest reduction.

Will compression hurt the quality?

High quality (CRF 23) is visually near-lossless. Balanced (CRF 28) is a great size-to-quality trade-off for sharing. Smallest (CRF 33 + downscale) prioritizes file size and is best for previews or messaging apps.

Why is compression slow for big files?

All processing runs locally in your browser with FFmpeg compiled to WebAssembly, which is single-threaded. For a smooth experience keep clips under about 100MB — larger videos can take several minutes.

Is my video uploaded anywhere?

No. Compression happens entirely on your device using WebAssembly. Your video never leaves your browser, so it stays private.

What format is the output?

The compressed file is always an MP4 using H.264 video and AAC audio — the most widely compatible combination for phones, browsers, and social platforms.

Video Compressor

Shrink video file sizes right in your browser without losing much quality. Fast, free, and private — nothing is uploaded.

Drag & drop your video file here

Supported: MP4, MOV, WebM, AVI, MKV

Runs entirely in your browser — for best speed keep clips under ~100MB.

How to Compress a Video

Reduce your video's file size in 3 simple steps.

Upload your video

Drag and drop or select an MP4, MOV, WebM, AVI, or MKV file.

Pick a compression level

Choose High quality, Balanced, or Smallest depending on your goal.

Compress & download

Run it, compare the before/after size, preview, and download.

Compression Tips

Get the best size-to-quality balance.

Start with Balanced

Balanced (CRF 28) usually cuts the size dramatically while keeping the video looking great — a solid default.

Go Smallest for Sharing

The Smallest preset also downscales to 1280px wide, ideal for messaging apps and email attachments.

Keep Detail with High

Use High quality (CRF 23) when you need near-lossless output and file size is a secondary concern.

Mind the File Size

Everything runs locally in WebAssembly, so clips under ~100MB compress fastest and most reliably.