MP4 to MP3 converter: pull the audio out of any video
Sometimes the video is just in the way: a recorded talk you want to hear on a walk, a webinar for your podcast feed, or the soundtrack of your own clip. Your todo.is agent extracts the audio from your MP4 files with ffmpeg, cleans it up a little and gives you MP3s with proper titles.
The prompt
- Extract the audio from the attached MP4 file(s) as MP3: [ATTACH THE MP4 FILES]. Use [BITRATE]. [TRIM]. Even out the volume so quiet and loud parts are closer, and cut silence longer than 3 seconds. Add MP3 tags: title [TITLE], artist [ARTIST]. Send me the MP3 and tell me its length and file size.
What to change
- [ATTACH THE MP4 FILES]: Attach one or more .mp4 files (up to 50 MB each). For bigger videos, send a link to a file you own.
- [BITRATE]: E.g. "128 kbps for speech", "192 kbps for music" or "320 kbps, best quality".
- [TRIM]: E.g. "cut the first 2 minutes of waiting", "only 14:00 to 52:00" or "keep it all".
- [TITLE]: E.g. "Q3 All-Hands, Oct 2026" or "use the file name".
- [ARTIST]: E.g. your name, the company or the speaker.
Example result
- MP4 to MP3: Q3 All-Hands
- Source: allhands_recording.mp4 · 58 min · 1080p
- Result: Q3_All_Hands_Oct_2026.mp3 · 54 min · 128 kbps · mono · 50 MB
- What your agent did
- • Extracted the audio track with ffmpeg; the video was ignored, so no picture data is in the file
- • Trimmed 3 minutes of "waiting for people to join" at the start and 1 minute after the goodbye
- • Silence: 9 pauses longer than 3 seconds were shortened, mostly while slides were loading
- • Volume: levelled to a podcast-style loudness, so the quiet speaker at 21:00 is as easy to hear as the host
- • Mono: the recording was the same on both channels, so mono at 128 kbps sounds like 256 kbps stereo for speech
- • Tags: title "Q3 All-Hands, Oct 2026", artist "Brightline Team", year 2026, so it shows properly in music and podcast apps
- Bitrate guide
- • 64 to 96 kbps mono: voice only, smallest files
- • 128 kbps: talks and podcasts, the usual choice
- • 192 kbps stereo: music
- • 320 kbps: the highest MP3 quality; only helps if the source audio is high quality
- Next steps you can ask for
- • "Transcribe it and give me the key points as a Word file"
- • "Split it into one MP3 per speaker section"
How to do it with todo.is
- Copy the prompt and choose the bitrate, trim and tags.
- Attach the MP4 in todo.is, or forward it to your agent on Telegram or email.
- Your agent extracts and cleans the audio and sends back the MP3.
- Ask for more, like "also make a 60-second highlight" or "transcribe it".
Tips for a better result
- For speech, 128 kbps mono is plenty. Higher bitrates mostly just make the file bigger.
- Only extract audio from videos you own or have permission to use, such as your own recordings.
- Levelling the volume makes a huge difference for recorded meetings where people sit at different distances from the mic.
- If the MP4 has several audio tracks (for example two languages), say which one you want.
MP4 to MP3 converter: FAQ
- Does converting MP4 to MP3 lose quality? MP3 is compressed, but at 128 kbps or more for speech and 192 kbps or more for music, most people cannot hear a difference from the video audio.
- Can I extract audio from a long video? Yes. Uploads can be up to 50 MB each; for longer videos, trim first or send a smaller export.
- Can I get WAV or M4A instead of MP3? Yes. Ask for WAV for editing or M4A for Apple devices.
- Can it transcribe the audio too? Yes. Ask for a transcript and your agent writes it out with timestamps.
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