FormatDrop
Video Format Comparison

AVI vs FLV: Legacy Container Comparison

AVI and FLV are both legacy video containers that have been superseded by MP4 and MKV. AVI (Audio Video Interleave) was Microsoft's standard for Windows video from 1992. FLV (Flash Video) was Adobe's format for web video, used by YouTube, Vimeo, and virtually every video site until HTML5 replaced Flash. Both are now dead formats, but millions of files in both formats still exist in archives.

AVIvsFLV

Quick Verdict

Use AVI when…

Use AVI (over FLV) if you must keep a legacy format — AVI still has broader software support than FLV now that Flash is retired. However, the correct choice for either is to convert both to MP4.

Use FLV when…

Neither format should be used for new content. Convert all FLV files to MP4 immediately — Flash is officially dead and FLV support is eroding rapidly across all platforms.

AVI vs FLV: Feature Comparison

FeatureAVIFLV
OriginMicrosoft (1992)Adobe/Macromedia (2002)
Primary useWindows desktop videoWeb video (pre-HTML5)
StatusLegacy, still readableDead (Flash retired 2020)
Modern browser supportNoNo
VLC supportYesYes
Common codecsDivX, Xvid, H.264Sorenson Spark, VP6, H.264
Max resolutionAny (codec-limited)Up to 1080p (H.264 FLV)
File sizeVaries (often large)Smaller (web-optimised)

When AVI wins

  • Origin: Microsoft (1992)
  • Primary use: Windows desktop video
  • Status: Legacy, still readable

When FLV wins

  • Origin: Adobe/Macromedia (2002)
  • Primary use: Web video (pre-HTML5)
  • Status: Dead (Flash retired 2020)

Frequently asked questions

How do I play FLV files now that Flash is gone?
VLC Media Player plays FLV files on all platforms without Flash. Download VLC from videolan.org and open the FLV file directly. For long-term storage, convert to MP4: `ffmpeg -i input.flv -c copy output.mp4` (lossless if the FLV contains H.264 and AAC).
Which is easier to convert — AVI or FLV?
Both are straightforward with FFmpeg. FLV to MP4 is often lossless if the FLV uses H.264 and AAC. AVI to MP4 may require re-encoding if the AVI uses old codecs like DivX or Xvid. Run `ffprobe` on the file first to check codecs.
Can I still upload FLV to YouTube?
No — YouTube stopped accepting FLV uploads around 2012 as it transitioned to HTML5. YouTube now accepts MP4, MOV, AVI, WMV, and several other formats. Convert FLV to MP4 before uploading to any modern platform.