FLV to MP3 converter
Extract MP3 audio from FLV video in seconds, free. No upload, no sign-up, no size limit: it runs in your browser.
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Quick answer: To extract MP3 audio from FLV video, add the FLV file to the iHateFiles FLV to MP3 converter and press Convert. The conversion runs in your browser, so the file is never uploaded, and it is free with no sign-up, watermark or size limit. Lifts the soundtrack out of the video and saves it as MP3. The picture is discarded; nothing is re-recorded.
Should you convert FLV to MP3?
Worth doing when you want the soundtrack of an FLV on its own: a podcast, an interview, a piece of music from a video. Choose a higher bitrate than you think you need, because the MP3 is encoded from the video's audio rather than from a master.
Taking the sound out of FLV
An FLV file holds Sorenson Spark, VP6 or H.264 from the Flash era. This keeps the sound, discards the picture, and writes the result as MP3 (MPEG-1 Layer III). The FLV original is not altered.
One more generation of compression
The sound inside an FLV is almost always compressed already. Re-encoding it as MP3 compresses it again, so set the bitrate at or above the original. For music, 192 kbps or more is a safe floor; for speech, far less is fine.
FLV and MP3 side by side
| FLV | MP3 | |
|---|---|---|
| Inside the file | Sorenson Spark, VP6 or H.264 from the Flash era | MPEG-1 Layer III |
| Compression | Lossy | Lossy |
| Carries sound | Yes | Yes |
| Plays on | VLC and very little else since Flash was retired in 2020 | everything, including car stereos and hardware twenty years old |
| Here | Read and write | Read and write |
What usually goes wrong
About the FLV. If you have FLV files they are probably old downloads worth rescuing, and converting them to MP4 is the way to keep them watchable.
About the MP3. Converting an MP3 to another lossy format compounds the damage, because the second encoder is guessing at audio the first one already threw away.
How to convert FLV to MP3
- Add your FLV file. It is read from your disk and stays there.
- Check the settings. The output format is already set to MP3.
- Press convert and the MP3 file is saved back to your device.
MP3 converter: everything that converts to MP3
Questions
How do I convert FLV to MP3?
Open this page, add your FLV file, and press convert. The file is decoded and re-encoded by your own browser and saved back to your device. Nothing is uploaded.
Is this FLV to MP3 converter free?
Yes, completely. There is no account, no sign-in, no watermark and no daily limit, because there is no server doing the work. Your own device does it.
Are my files uploaded anywhere?
No. There is no upload endpoint. The conversion runs inside this browser tab, so your file never leaves your device. You can open your browser's network panel and watch: nothing carrying your file is sent.
Is there a file size limit?
No fixed limit. Because the work happens on your machine there is no server quota. The only ceiling is your own device's memory, which for video means very large files may be slow.
Does extracting audio reduce the quality?
The soundtrack is re-encoded to MP3, so there is one generation of loss at the bitrate you choose. Pick a higher bitrate, or a lossless target like WAV or FLAC, to avoid it.
Can I convert several FLV files at once?
Yes. Add as many as you like and they are converted one after another, then offered as a single ZIP.