Convert FLV to MP4
Convert FLV files to MP4 locally, completely free and with maximum privacy.
Drag and drop your files here
or click to browse local files (large files supported, limited only by browser RAM)
Upload FilesPlatform Statistics
How to convert FLV to MP4
- Drop your .flv files above, or click Upload Files. You can add many files at once.
- MP4 is already selected as the output. Open the settings (gear icon) to fine-tune the result.
- Click Convert All. FFmpeg runs inside your browser through WebAssembly; nothing is uploaded.
- Download your .mp4 files as soon as each one finishes.
What to know about FLV to MP4 conversion
- The video is re-encoded to H.264 video and AAC audio so it plays wherever MP4 is supported, and odd frame sizes are adjusted automatically.
- You can change the resolution, frame rate, playback speed and quality (CRF) before converting.
FLV vs MP4
| Feature | FLV (Flash Video) | MP4 (MPEG-4 Part 14) |
|---|---|---|
| Codecs used by PureConverter | H.264 video and AAC audio | H.264 video and AAC audio |
| Best for | legacy Flash-based players and old streaming setups | sharing and streaming video on any device |
| Opens in | VLC, mpv and most media players | every browser, phone, TV and media player |
FLV (Flash Video): A legacy streaming video container popularised by Adobe Flash Player.
MP4 (MPEG-4 Part 14): A widely compatible digital multimedia container format, most commonly used to store video and audio.
Conversion options
- Resolution: original, 1080p, 720p, 480p or 360p
- Frame rate and playback speed (0.5× to 2×)
- Quality presets or a custom CRF value, and lossless mode
- Audio bitrate, sample rate and channels
Frequently asked questions
Is it safe to convert FLV to MP4 here?
Yes. Your files are processed entirely on your own device by WebAssembly code running in the browser. They are never uploaded, so nobody else can see them, and the converter keeps working even if your connection drops after the page loads.
Is there a file size limit?
There is no server-side limit. The only limit is the memory available to your browser, typically 1.5–4 GB on desktop computers.
Can I convert several FLV files at once?
Yes. Add as many files as you like; they are converted in parallel according to your device's CPU cores, and you can apply the same settings to all of them.
Related conversions
Need the opposite? Convert MP4 to FLV.
Convert FLV to other formats
- FLV to MP3
- FLV to WEBP
- FLV to GIF
- FLV to WAV
- FLV to MOV
- FLV to M4A
- FLV to FLAC
- FLV to WEBM
- FLV to MKV
- FLV to AAC
- FLV to OGG
- FLV to OPUS
Convert other formats to MP4
- MOV to MP4
- WEBM to MP4
- MKV to MP4
- AVI to MP4
- WMV to MP4
- M4V to MP4
- MPEG to MP4
- TS to MP4
- 3GP to MP4
- OGV to MP4
See every FLV converter and MP4 converter, or browse the full converter directory.