MP4 vs FLV
How do MP4 and FLVcompare? Here's everything you need to know to choose the right format — and how to convert between them.
.mp4
Full guide →MPEG-4 Part 14
MP4 is the most widely used video format in the world. It's the default for everything from YouTube to TikTok, smartphones to streaming services. If you need one video format that works everywhere, MP4 is it.
.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 | MP4 | FLV |
|---|---|---|
| Full name | MPEG-4 Part 14 | Flash Video |
| Extension | .mp4 | .flv |
| MIME type | video/mp4 | video/x-flv |
| Category | Video | Video |
| Developer | ISO / Moving Picture Experts Group | Adobe (Macromedia) |
| Year introduced | 2001 | 2003 |
MP4 advantages
- Universal compatibility
- Excellent compression with H.264/H.265
- Supports subtitles and multiple audio tracks
- Streaming-friendly with progressive download
MP4 limitations
- Lossy compression
- Patent-encumbered codecs
- Quality varies greatly by encoding settings
- Large files at high quality
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- Outdated codec support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?
MP4 is the universal standard — it works everywhere. FLV has its niche: converting old web videos. When in doubt, convert to MP4 for maximum compatibility.
Best uses for MP4
Best uses for FLV
Convert between MP4 and FLV
Need to switch formats? Convert for free with SquishConvert.