FLV to MP4 Converter
Flash Player is gone, but the FLV files it played are still on old hard drives, backup discs and archived websites. Converting them to MP4 lets any phone, browser or editor open them again.
Video Converter
or drop MP4, MOV, MKV … files here ·
Max 95 MB per file· Up to 20 files· Deleted after 30 minutes
Files are processed on our servers and deleted after 30 minutes.
Lower is better quality and a bigger file. 18 looks identical to the source, 23 is the default, 28 and above shows visible softening.
Frames per second. Keep the source rate unless a platform asks for a specific one; 15–20 fps is plenty for GIFs.
Only used for PowerPoint files and single still images: how long each slide or picture stays on screen.
Auto uses AAC for MP4/MOV and Opus for WebM. Copy keeps the original sound untouched when the new format supports it.
192 kbps is transparent for music; 128 kbps is enough for speech.
Width of the animation in pixels; height follows the aspect ratio. 480 px suits chats, 720 px or more gives a high-quality GIF but a much larger file.
GIF holds at most 256 colors. Fewer colors make a smaller file but cause banding on gradients and skin tones.
Mixes palette colors in a fine pattern to hide banding. Sierra gives the smoothest result; none gives the smallest file.
Whether the animation repeats endlessly or plays one time and stops.
Optional. Seconds (e.g. 75) or minutes:seconds (1:15). Leave empty to start at the beginning.
Optional. Same format as the start time. Leave empty to keep everything up to the end.
The converted file will be at or just under this size.
How to use this tool
- 1
Add the FLV files
Drop .flv or .f4v files on the upload area, up to 20 per batch and 95 MB each.
- 2
Leave the defaults
The page writes H.264 at Quality (CRF) 22 with AAC sound at 128 kbps, which is more than these low-resolution clips need.
- 3
Convert and save
Press Convert to MP4 and download each video.
Upload the FLV, press Convert to MP4, and the Flash-era clip comes back as an H.264 video that plays everywhere, with no plugin involved.
What Flash Video was and why FLV stopped playing
For most of the 2000s, video on the web meant Flash. Early YouTube, news sites and e-learning platforms delivered FLV files to the Flash Player plugin, and download tools saved those files straight to disk. Webcam chats and live streams recorded to FLV too, and RTMP, the streaming protocol many platforms still use for ingest, carries video in FLV packets.
Adobe announced the end of Flash in 2017, stopped supporting it on December 31, 2020 and blocked Flash content from running on January 12, 2021. Browsers removed the plugin, and with it the only player most people had for FLV.
FLV from Flash Player 6 to end of life
2002
Flash Player 6
FLV arrives with the Sorenson Spark codec, a variant of H.263.
2005
Flash Player 8
On2 VP6 adds sharper video and an optional alpha channel.
2007
Flash Player 9 Update 3
H.264 video, AAC audio and the F4V container are supported.
2017
End announced
Adobe says Flash will be retired at the end of 2020.
2020
End of life
Support ends on December 31; content is blocked from January 12, 2021.
FLV
Flash Video
FLV is the Flash Video container that Macromedia, later Adobe, introduced in the early 2000s for streaming video in Flash Player. It powered early YouTube and many video sites, and the FLV format is still used by some RTMP live-streaming tools. With Flash Player discontinued in 2020, browsers and phones no longer play FLV files. VLC and other desktop players still open them.
- Compression
- Lossy
- Transparency
- –
- Animation
- –
- Introduced
- Macromedia (now Adobe)
MP4
MPEG-4 video
MP4 (MPEG-4 Part 14) is a multimedia container standardised by ISO/MPEG and based on Apple's QuickTime format. It usually holds H.264 or HEVC video with AAC audio, and can also carry subtitles, chapters and metadata. It is the most compatible video format in the world, playing on phones, browsers, TVs, game consoles and social platforms. The video inside is almost always lossy, so repeated re-encoding gradually reduces quality.
- Compression
- Lossy
- Transparency
- –
- Animation
- –
- Introduced
- 2001 · Moving Picture Experts Group (MPEG)
FLV goes to MP4 because Flash Player no longer exists: the clip is a leftover from a 2000s website or download and needs a container that today's devices still decode.
Codecs you may find inside an FLV file
| Codec | Kind | Added in | Where it came from |
|---|---|---|---|
| Sorenson Spark (H.263) | Video | Flash Player 6, 2002 | Early video sites and webcam clips |
| On2 VP6 | Video | Flash Player 8, 2005 | Flash 8 exports and mid-2000s players |
| H.264 | Video | Flash Player 9 Update 3, 2007 | Later streams and HD Flash video |
| MP3 | Audio | Flash Player 6, 2002 | Most music and lecture FLVs |
| Nellymoser, Speex | Audio | Player 6 and 10 | Microphone input in chat and conference tools |
| AAC | Audio | Flash Player 9 Update 3, 2007 | Paired with H.264 video |
Whatever the FLV holds, the MP4 gets H.264 video and AAC audio at the original frame size and frame rate. Sorenson and VP6 clips from before 2007 are small and low-resolution, so they convert quickly and the MP4 is usually close to the FLV's size; H.264 FLVs keep their HD resolution.
A pile of old clips from a backup drive can go through in batches of 20. If some files are other legacy formats, such as camcorder AVIs or Windows Media files, WMV to MP4 and AVI to MP4 work the same way.
FLV to MP4 questions
Can I still play FLV files now that Flash is dead?
Yes, in a stand-alone player such as VLC or mpv, which decode FLV without Adobe's plugin. Browsers, phones, smart TVs and video editors cannot, and that is where converting to MP4 helps.
Will my old FLV look better as an MP4?
No, but it will not look worse at the default settings. Most FLV files from the 2000s are 320 × 240 or 480 × 360 pixels, and the converter keeps that size rather than inventing detail. Watch them in a smaller window and they look as they did.
What is an F4V file?
F4V was Adobe's second Flash container, introduced with Flash Player 9 Update 3 in 2007. It is built on the same ISO base format as MP4 and carries H.264 and AAC, so it converts cleanly here as well.
Why do some FLV files play with no sound?
Webcam recordings from Flash-era chat and conferencing tools often used Nellymoser or Speex audio, which few modern players decode. The converter rewrites the sound as AAC, which every MP4 player supports.
Is FLV the same as SWF?
No. FLV holds only video and audio, while SWF is a Flash program that can contain vector animation, code and interactive buttons. Convert SWF animations with SWF to MP4; interactive parts such as games cannot become a video.
Can I keep just the audio from an FLV?
Yes. Old music videos and lectures are often wanted only for their sound; FLV to MP3 extracts the track without the picture.
| SWF to MP4 | WMV to MP4 | AVI to MP4 |
| MPEG to MP4 | 3GP to MP4 | VOB to MP4 |
| M4V to MP4 | MOV to MP4 | Video converter |