FormatDrop
Video Format

FLV

Flash Video

FLV (Flash Video) was the dominant web video format from the mid-2000s until HTML5 video replaced Flash around 2015. YouTube, Vimeo, and virtually every video website used FLV. If you have old video downloads from that era — YouTube rips, screencasts, webinars, streaming video captures — they're probably FLV. Flash is dead; FLV files need to be converted to MP4.

What is FLV?

FLV was developed by Macromedia (acquired by Adobe in 2005) as the container format for the Flash Video codec (Sorenson Spark, then On2 VP6). It was designed to be delivered by Flash Media Server and played back in the Adobe Flash Player browser plugin. FLV files contain: video encoded in Sorenson H.263 (early FLV), On2 VP6 (better quality FLV), or H.264 (later FLV, actually using the F4V variant), and audio encoded in MP3, AAC, or older Flash Audio codecs. The Flash Player plugin enabled video playback at a time when browsers had no native video capabilities. This made FLV the universal web video format for nearly a decade. YouTube launched with FLV in 2005 and switched to HTML5 video (MP4) around 2010–2015. Adobe officially ended Flash Player support on December 31, 2020. Since then, no major browser supports Flash, making FLV playback impossible in browsers without third-party players. FLV files remain accessible via VLC, FFmpeg, and desktop players, but they're a legacy format with no modern use cases.

FLV pros and cons

Advantages

  • Universal understanding — every FFmpeg and VLC version handles FLV
  • Small file sizes at the quality levels it was designed for (SD streaming)
  • Historical archive value — contains web content from 2005–2015

Limitations

  • Adobe Flash Player is dead — no browser support
  • Not supported on iOS, Android, smart TVs, or any modern device
  • Older video codecs (Sorenson H.263, VP6) are lower quality than H.264
  • No native support in any modern browser or media player without plugins
  • Actively obsolete — no new content should be created in FLV

When should you convert FLV files?

Convert FLV to MP4 immediately. There is no use case for keeping video as FLV in 2024. FLV files should be converted to H.264 MP4 for playback on any modern device. The conversion is straightforward — most FLV files can be remuxed or encoded to MP4 with good quality, depending on the source codec. FLV files with H.264 video (F4V-style) can often be remuxed without re-encoding. FLV with Sorenson H.263 or VP6 requires re-encoding to H.264.

Convert FLV files

VIDEO-CONVERTER→

All FormatDrop conversions run entirely in your browser — no file upload, no server processing. Your files stay on your device.

FLV FAQ

How do I convert FLV to MP4?
FormatDrop's video converter handles FLV to MP4 in your browser. FFmpeg (command line): ffmpeg -i input.flv -c:v libx264 -c:a aac output.mp4. VLC: Media → Convert/Save → add FLV file → convert to MP4 H.264. HandBrake (free GUI): open FLV file, select MP4 output, encode.
Why won't my FLV file play?
Modern browsers don't support Flash/FLV playback. To play FLV files: use VLC Media Player (free, plays FLV on Windows, Mac, Linux). Or convert to MP4 first. Trying to play FLV in Chrome, Edge, Firefox, or Safari won't work — these browsers removed Flash support in 2019–2021.

More formats

HEICWebPAVIFEPUBWebMOpusMP3WAVM4AFLACAACMP4AVIMKVMOVJPGPNGGIFSVGTIFFICOBMPEPSARWOGGWMVPPTXPagesPDFDOCXRAWHEVCH.264AIFFM4VWMA3GPDNGRTFPSDOGVTSAIXLSXCSVZIPAPNGMIDIJPEG XLMPG/MPEGVOBM2TSAC3ALACDTSJP2HEIFAPECBZ3G2SRTDOCPPTXLSODTODSM3URAR7ZM4BAMRTXTMOBITARGZJSONXMLYAMLKEYMTSCR2NEFMXFTGACAFASSVTTDSFRMF4VWVASFRMVBORFRW2EAC-3TTAISODMGXZDjVuFB2AUM4RAZW3MKAEXRVCFICSAAXPRCMP2SPXXSPFM3U8