Compress an audio file to email or send it

Most email providers stop at around 25 MB, and chat apps are stricter. A one-hour WAV is about 350 MB, so it needs to get smaller before it goes anywhere.

Compress a recording

1. Open the recording in the player.
2. Tap Compress in the tool row.
3. Choose a target quality — lower bitrate and sample rate mean a smaller file.
4. Check the estimated size shown before you commit.
5. Save as a copy, then share the copy and keep the original.

How small to go

• One person talking survives 64 kbps mono easily — about 28 MB an hour.
• Two or more voices in a room: 96–128 kbps mono.
• Music: do not compress below 192 kbps, and keep the original.
• Halving the sample rate saves as much as halving the bitrate, and on speech it is less audible.

Other ways to make it fit

• Trim the dead air first — it is free and it can be a surprising share of a long take.
• Cut the file into parts and send them separately.
• Share a link from the Files app or iCloud Drive instead of attaching the file.
• Send the transcript instead, when the text is really what the other person wants.