Format comparison
WebM vs FLV
How do WebM and FLVcompare? Here's everything you need to know to choose the right format — and how to convert between them.
.webm
Full guide →Web Media
WebM is Google's open-source video format designed specifically for the web. It offers excellent compression and quality, especially with the VP9 and AV1 codecs, and is royalty-free.
.flv
Full guide →Flash Video
FLV was the dominant web video format during the Flash era. While Flash is dead, FLV files still exist in archives and legacy systems. Converting FLV to MP4 is one of the most common conversion needs.
| Specification | WebM | FLV |
|---|---|---|
| Full name | Web Media | Flash Video |
| Extension | .webm | .flv |
| MIME type | video/webm | video/x-flv |
| Category | Video | Video |
| Developer | Adobe (Macromedia) | |
| Year introduced | 2010 | 2003 |
WebM advantages
- Royalty-free and open source
- Excellent web browser support
- Great compression with VP9/AV1
- Designed for HTML5 video
WebM limitations
- Limited support outside web browsers
- Fewer editing tools available
- Hardware decoding less common
- Less universal than MP4
FLV advantages
- Very small file sizes
- Fast to decode
- Was the web video standard
- Simple container format
FLV limitations
- Flash Player is discontinued
- Limited browser support
- Outdated codec support
- No modern features
Which should you use?
WebM and FLV target different use cases. WebM is ideal for html5 web video, while FLV works best for converting old web videos.
Best uses for WebM
HTML5 web video
YouTube (internal format)
Web applications
Open-source projects
Best uses for FLV
Converting old web videos
Legacy content archives
Flash game recordings
Historical web content preservation
Convert between WebM and FLV
Need to switch formats? Convert for free with SquishConvert.