The three settings that shrink a video

  1. Resolution. The biggest saving. Going from 4K to 1080p cuts the file to roughly a quarter; 720p is still sharp on a phone screen and smaller again.
  2. Quality. Choose Small file instead of Balanced. The picture gets slightly softer, which is hard to notice on a phone.
  3. Length. Trim the start and end. Half the length is half the size.

Frame rate helps a little too: 30 frames per second instead of 60 makes a smaller file and looks the same for most clips.

Step by step

  1. Open the MP4 compressor (MP4 to MP4). For iPhone videos, use MOV to MP4, which also makes the video play on Windows and Android.
  2. Drop the video in and open the settings next to MP4.
  3. Set Resolution to 720p or 1080p and Quality to Small file. Add trim points if you only need part of it.
  4. Select Convert, check the new size, and download.

Still too big? Run it again at a lower resolution, or trim it shorter.

Rough sizes to aim for

  • Email: under 20 MB to be safe with Gmail, Outlook and most work email.
  • WhatsApp: the smaller the better; WhatsApp compresses videos again when sending them as media. To keep full quality, send the file as a document instead.
  • At 720p and Small file, a minute of video usually comes out somewhere around 10–20 MB, depending on how much movement there is.

Only need the sound?

If it's a lecture, interview or voice recording, send just the audio: extract it as an MP3, which is usually ten times smaller than the video.