Extract Audio from Video Online Free - MP4 to MP3 Converter
Extract audio tracks from video files and save as MP3, M4A, WAV, or FLAC. Browser-local processing with no upload. Step-by-step guide.
Short answer: Yes—use NanoPix Extract Audio. Drop a video file, pick your audio output format, and download. No upload, no account, completely free.
How to extract audio in 3 steps
- Open Extract Audio and import your video. Supported formats: MP4, MOV, MKV, AVI, WebM, FLV, and more.
- If the video has multiple audio tracks (e.g., different language tracks or commentary), choose the specific track you want.
- Select output format (M4A, MP3, WAV, or FLAC) and click Export.
Supported output formats comparison
| Format | Codec | Quality | File size | Best for |
|---|---|---|---|---|
| M4A | AAC | Excellent | Medium | Best overall balance, broad compatibility |
| MP3 | MPEG-1 Layer 3 | Good to very good | Small | Universal playback, smaller files |
| WAV | PCM (uncompressed) | Perfect | Very large | Editing, archival, lossless master |
| FLAC | FLAC (lossless) | Perfect | Large (compressed lossless) | Archival, open format |
Common use cases
- Music videos → extract the song as MP3 for offline listening
- Meeting recordings → save audio for transcription services
- Video lectures → listen as audio-only podcasts on the go
- Voiceovers → extract narration for reuse in other projects
- Movie clips → save dialogue or sound effects
Local vs cloud extraction
| Feature | Cloud extractor | NanoPix local |
|---|---|---|
| File upload | Full video uploaded to server | No upload needed |
| Privacy risk | Server processes your entire file | Stays on your device |
| Format options | Often limited on free tiers | 4 output formats, all free |
| Processing speed | Depends on upload speed + server queue | Starts immediately, local speed |
| File size limits | Common caps (500MB) | Limited by your RAM only |
Audio track selection
If your video has multiple audio tracks (common in MKV files with multi-language support, or MP4 files with commentary tracks), NanoPix lets you choose exactly which track to extract. This is useful for:
- Extracting a specific language from a multilingual video
- Saving commentary tracks separately
- Isolating different microphone recordings
Related tools
- Audio Convert — convert extracted audio between formats
- Audio Trim — cut unwanted sections from extracted audio
- Add Audio to Video — combine extracted audio back with other video
FAQ
Can I extract audio from MP4 for free?
Yes. NanoPix is completely free with no limits, no watermark, and no account required.
Which audio format has the best quality?
WAV and FLAC are lossless (perfect original quality). M4A/AAC offers excellent quality at much smaller file sizes. MP3 is universal but slightly lower quality at the same bitrate.
Can I choose which audio track to extract?
Yes. If the video has multiple audio tracks (different languages, commentary, etc.), you can select the specific track before export.
Is it safe to extract audio from private videos online?
Yes. NanoPix processes everything locally in your browser. Your video never reaches any server.
Can I extract audio from an online video URL?
No. NanoPix works with local files only. Download the video to your device first.
How long does audio extraction take?
Audio extraction is much faster than video re-encoding since only the audio track is processed. Most files complete within a minute.