How much smaller will my file be?

It depends on the source, but a phone video at CRF 30 with a 720p cap often drops by 60–80%. Compare the before/after sizes shown in the queue.

Does compressing reduce quality?

Some detail is always lost when re-encoding, but at moderate CRF values the difference is hard to see while the file shrinks a lot.

Compress a video

Reduce video file size in your browser. Pick a quality level and an optional resolution cap, and get a smaller MP4 — no upload, no watermark.

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How compression works

The tool re-encodes your video with H.264 at a chosen CRF (Constant Rate Factor). A higher CRF discards more detail for a smaller file; a lower CRF keeps quality high. Capping the resolution shrinks large 4K clips dramatically.

Why compress a video?

Smaller files upload faster, fit under email and chat limits, and stream more smoothly. Compressing is the fastest way to get a phone recording under a 25 MB attachment cap.

Choosing settings

CRF 28 is a good default balance. Try 23–26 when quality matters, or 32–36 for aggressive size cuts. Cap resolution at 1080p or 720p when the source is larger than you need.

How to compress video

Drop the video you want to shrink.
Set the compression slider and, optionally, a maximum resolution.
Press Convert and download the smaller MP4.

Related converters

Resize VideoFit a video to landscape, story, or square social presets.MP4 to WebMTurn MP4 videos into open, web-friendly WebM (VP9/Opus).Trim VideoCut a clip to a start and end time without re-encoding.