MP4 to MP3 Converter

How to Convert MP4 to MP3 Online

1. Upload Your MP4 Video: Click "+ Add Files" or drag and drop MP4 (and M4V) videos from your computer. Batch upload is supported — every file in the queue uses the same export settings.
2. Pick Bitrate Mode and Quality Preset: Under Advanced Options, choose Constant Bitrate (CBR) for predictable file size or Variable Bitrate (VBR) for better quality-per-byte. Then use the Preset dropdown — Highest (320 kbps CBR / V0 VBR) for music, High (192-256 kbps) for general listening, Medium (128 kbps) for podcasts and speech, or Custom Bitrate to set an exact value from 8 to 320 kbps.
3. Adjust Channels, Sample Rate, or Trim (Optional): Leave Audio Channel and Audio Sample Rate on "Original" to match the source, or downmix to Mono and resample to 44100 Hz / 48000 Hz. Use the Trim controls to set a Start (HH:MM:SS.MS) and Duration if you only want a portion — useful for ringtones, sermon clips, or song extracts.
4. Convert and Download: Click Convert. Files are processed on our servers over HTTPS and removed shortly after — no sign-up, no watermark, no install. Download individually or grab the whole batch as a zip.

Why Convert MP4 to MP3?

MP4 is a container that almost always carries AAC audio alongside H.264 or H.265 video — great for playback on phones and TVs, but oversized when you only need the soundtrack. MP3 is a lossy audio-only format that has remained universally supported by car stereos, MP3 players, smart speakers, DAWs, podcast hosts, and every operating system since the late 1990s. Extracting the audio drops file size by 90-95% and lets the audio travel anywhere video can't.

• Listen to music videos offline — Pull the audio from a concert recording, live session, or official music video so you can play it on a phone, smartwatch, Bluetooth car stereo, or older MP3 player that does not handle MP4 video tracks.
• Build podcast episodes from recorded video — Strip the audio from Zoom recordings, webinars, or interview footage so it uploads cleanly to podcast hosts like Buzzsprout, Spotify for Podcasters, or Libsyn, which accept MP3 natively.
• Save lecture and meeting audio — A 1-hour 1080p lecture MP4 is typically 1-2 GB; the same audio as a 128 kbps MP3 is roughly 55 MB, small enough to email or store on a phone for review on the commute.
• Make ringtones and notification clips — Trim a 5-30 second segment from a music video MP4 and export to MP3; many Android phones still accept MP3 directly as a ringtone source.
• Prep audio for editing or transcription — DAWs like Audacity, Reaper, and Logic, plus transcription tools like Otter.ai and Descript, all import MP3 faster than parsing a video container.
• Feed audio into AI tools — Speech-to-text APIs (OpenAI Whisper, AssemblyAI, Deepgram) accept MP3 directly and process it faster than re-decoding video.

MP4 Audio Track vs MP3 Output

MP3 Bitrate Cheat Sheet (1-Hour Source)

Speech vs Music — Pick the Right Settings

For the reverse direction or other targets, see MP3 to WAV, MP4 to WAV (lossless), MP4 to FLAC, MP4 to AAC, or MP4 to M4A. Already have an MP3 that's too big? Try Compress MP3.

Frequently Asked Questions

Will the MP3 sound worse than the original MP4 audio?

The MP4 almost certainly contains AAC, which is already lossy. Going AAC to MP3 is a transcoding step — there is some quality loss, but at 192 kbps MP3 or higher most listeners cannot tell the difference from the source on consumer speakers or earbuds. The source bitrate is the ceiling: re-encoding a 128 kbps AAC track at 320 kbps MP3 does not add detail back; it only inflates file size.

What bitrate should I pick for a YouTube music video MP4?

YouTube's stereo AAC audio for 1080p uploads is typically 128-192 kbps. Encoding to MP3 at 192-256 kbps captures everything the source has to offer; 320 kbps wastes space without adding fidelity. For a 1080p60 or 4K source with stereo Opus/AAC, 256-320 kbps MP3 is a safe choice if you want maximum headroom.

Why is the MP3 bigger or smaller than I expected?

File size depends on bitrate and duration, not on the original video size. A 1-hour MP4 at 1080p might be 2 GB, but a 1-hour 192 kbps MP3 is always close to 85 MB regardless of whether the source was 720p or 4K. If your output looks tiny, the source audio may have been very short or mono — check the trim settings and channel dropdown.

Can I extract only part of the video as MP3?

Yes — use the Trim controls under Advanced Options. Set the Start point (HH:MM:SS.MS format) and Duration to pull a single song from a long concert MP4, a 30-second hook for a ringtone, or just the Q&A section of a webinar. For more advanced cutting after conversion, use the MP3 trimmer; to trim the video first, see the video trimmer.

Should I pick CBR or VBR?

Constant Bitrate gives predictable file sizes and broadest legacy hardware compatibility (older car stereos, hardware MP3 players), which is why streaming and podcast platforms still default to it. Variable Bitrate produces smaller files at the same perceived quality by allocating more bits to complex passages — best when you want maximum quality per megabyte and your playback device is from the last decade.

Why does my MP4 fail to convert?

The most common cause is the audio stream uses an unusual codec or the file uses a fragmented MP4 (fMP4) variant from a DRM-protected stream. Files downloaded from streaming services may carry encrypted audio tracks that no converter can extract. Try re-saving the file with a desktop tool first, or upload an MP4 that plays normally in VLC or QuickTime.

Will tags, chapter markers, and cover art carry over?

Basic metadata (title, artist, album if present in the MP4) is mapped to ID3v2 tags on the MP3. Cover art embedded in the MP4 moov atom is preserved when present. MP4 chapter markers do not have a clean MP3 equivalent — MP3 supports chapter frames via ID3v2 but most players ignore them; if chapters matter, M4A (AAC) is a better target.

Is converting MP4 to MP3 legal?

Extracting audio from a video you own or have rights to use is fine. Pulling audio from copyrighted music videos, paid streaming services, or DRM-protected content for redistribution is not — most jurisdictions treat that as a copyright violation. Personal-use ripping rules vary by country (e.g., permitted in the US under fair use in limited cases, restricted in Germany, allowed for private copies in France with levies). Check the rules where you live.

Does the audio stay in sync if I had A/V drift in the MP4?

Audio extraction reads the audio track at its native timestamps, so any drift baked into the original MP4 will carry over. If the source video had visible lip-sync issues, the MP3 will start at the same absolute time but won't "fix" the drift. For files with bad timestamps, re-mux the MP4 with ffmpeg or a desktop tool first, then extract.