WebM to FLV Converter
Convert WebM to FLV free — no upload, no signup
To convert WebM to FLV, drop your WebM video into the box below and click Convert. Fylo converts with ffmpeg running inside your browser, so nothing is uploaded and there's no signup or watermark. Encode WebM into H.264 FLV for streaming tools.
Drop videos here
or tap to browse · paste with Ctrl+V · add many at once
Your files never leave your device
If the video already uses codecs that fit the new format, Fylo repackages it instantly with no quality loss.
Advanced
How to convert WebM to FLV
Add your WebM videos
Drag and drop WebM files into the box or tap to choose them. The converter engine (about 31 MB) downloads once, the first time you convert.
Choose quality (optional)
Balanced quality suits most videos. If the codecs already fit FLV, Fylo repackages the file instead of re-encoding it, with no quality loss.
Convert and download
Click Convert, then download each FLV file or all of them as one ZIP.
Why convert WebM to FLV?
If an RTMP streaming tool or legacy portal needs FLV, this converts WebM recordings into something it accepts.
What happens when you convert WebM to FLV?
VP8/VP9 isn't supported in FLV workflows, so Fylo re-encodes to H.264 with 44.1 kHz AAC audio.
How does Fylo convert WebM to FLV?
Fylo reads the WebM with ffmpeg compiled to WebAssembly and writes H.264 with AAC audio at 44.1 kHz, the sample rate Flash-era players expect. WebM's usual codecs (VP8, VP9, AV1) can't go into FLV as-is, so the video is re-encoded. Speed depends on your device: short phone clips take seconds, while on our slow test PC a 2-minute 1080p video took about 10 minutes. Only the first video and audio track are kept, and the original resolution is preserved unless you pick 1080p, 720p or 480p under Advanced.
What's the difference between WebM and FLV?
WebM was announced by Google in 2010 as an open, royalty-free alternative to H.264 for HTML5 video. It's a subset of Matroska restricted to VP8, VP9 or AV1 video and Vorbis or Opus audio. Browser screen recorders and many web tools save WebM by default.
FLV (Flash Video) was introduced with Flash Player 6 and 7 in 2002–2003 and became the format behind early YouTube, news sites and video portals. Later FLVs usually contain H.264 video and AAC audio — the same codecs as MP4.
Learn more: WebM format guide · FLV format guide
| Property | WebM | FLV |
|---|---|---|
| Developed by | Macromedia / Adobe | |
| Introduced | 2010 | 2003 |
| Typical video codecs | VP8, VP9, AV1 | H.264, Sorenson Spark, VP6 |
| Typical audio codecs | Vorbis, Opus | AAC, MP3 |
| Plays in web browsers | Yes — Chrome, Edge, Firefox, Safari 14.1+ | No (Flash Player ended in 2020) |
| Compatibility | Browsers, Android; limited in editors and on iPhone apps | VLC and some desktop players; RTMP live-streaming tools |
| Best for | Royalty-free web video, screen recordings | Old Flash archives, RTMP streaming workflows |
Frequently asked questions
Is FLV still used?
Mostly inside streaming software; browsers no longer play it.
Will audio be converted?
Yes, Opus or Vorbis becomes AAC.
Is my WebM file uploaded to a server?
No. Fylo runs ffmpeg, the same engine used by professional video tools, compiled to WebAssembly inside your browser. Your WebM file is read directly from your device and never sent anywhere.
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