Add your 3GP file
Drop one or more .3gp files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Pulling the soundtrack out of a .3gp video into .flv audio keeps what you can hear and drops the picture entirely. Free, private, and validated — the file never leaves your browser.
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.Pulling the soundtrack out of a .3gp video into .flv audio keeps what you can hear and drops the picture entirely. A .3gp file is a lightweight container defined by the 3GPP standards body for video recorded and shared on mobile phones. It packs low-bitrate video and compressed speech with minimal overhead, which made .3gp the format of MMS messages and early camera phones.
An .flv file is a Flash Video container, the format that powered most web video during the 2000s. YouTube, news sites, and early streaming platforms delivered .flv streams into the Flash Player plugin before HTML5 video replaced the whole stack. For this route the practical draw is very small container overhead and h.264/AAC content re-wraps to MP4 without any re-encoding — balanced against no mainstream player ships FLV support anymore, which is worth knowing before you commit a large batch.
The usual reason to take .flv audio out of a .3gp file is that only the sound matters — a talk, interview, song, or podcast segment. Keeping the video stream would waste storage, and a dedicated audio file is easier to trim, tag, and play. On the source side, picture quality is poor by any modern standard; on the target side, the payoff is very small container overhead, which is exactly what you want for recovering clips downloaded during the Flash era.
| Aspect | 3GPP video (.3gp) | Flash video (.flv) |
|---|---|---|
| Format type | Container — quality depends on the codecs and settings inside | Container — quality depends on the codecs and settings inside |
| How it stores data | iSO base media structure like MP4, but with a deliberately restricted codec list | a simple sequence of tagged audio, video, and script packets designed for progressive download and RTMP streaming |
| Strongest at | recovering videos from old feature phones and their memory cards | recovering clips downloaded during the Flash era |
| Weak spot | picture quality is poor by any modern standard | no mainstream player ships FLV support anymore |
| Metadata | a small set of 3GPP-defined asset atoms for title, author, and location exists, though most recording phones never wrote them | an onMetaData script tag embeds duration, dimensions, and encoder details; there is no standard field set for titles or authorship |
Drop one or more .3gp files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Select .flv in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if FLV is selectable, the route is real and validated.
Press Convert. A WebAssembly FFmpeg build demuxes the audio track and re-encodes it locally; the video stream is simply discarded.
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid FLV file. Outputs keep the original filename with the .flv extension.
Since 3gp is container-oriented and flv is container-oriented, the conversion preserves the source content exactly as stored; no additional compression pass is applied beyond what .flv itself requires.
Yes — the .3gp file is processed inside your browser tab and never uploaded. A WebAssembly FFmpeg build demuxes the audio track and re-encodes it locally; the video stream is simply discarded. Close the tab and the file is gone from memory.
No current browser can play .flv, since the plugin that decoded it was removed from Chrome, Firefox, and Edge at the end of 2020. VLC and ffmpeg-based tools still read the format reliably, which is how old files get rescued into MP4.
Much smaller — the video stream is usually 80–95% of a .3gp file's weight, and it is discarded entirely. The remaining audio is re-encoded at the bitrate implied by your quality setting.
This converter strips container metadata deliberately (the FFmpeg command runs with metadata mapping disabled) so exported files do not leak recording details. In the source, a small set of 3GPP-defined asset atoms for title, author, and location exists, though most recording phones never wrote them; none of it is transmitted anywhere because the file never leaves your browser.
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .3gp → .flv → .3gp is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.