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FLV to MP4 (H.264) - Online Video Converter
Convert FLV to MP4 (H.264) online. Private, client-side - no uploadrequired. Batch conversion, quality presets, codec control.
Convert FLV to MP4 (H.264)
Drop FLV video here or click to select
FLV
MP4 (H.264) (H.264 / AAC)
About FLV to MP4 (H.264)
FLV is Flash-era packaging, so MP4 carries the same H.264 picture into current players.
Why convert FLV to MP4 (H.264)?
- Smaller files with MP4 lossy compression.
- Keep animation and transparency where supported.
- Private, no upload - runs in your browser.
FLV vs MP4 (H.264)
| Animation | Yes | Yes |
|---|---|---|
| Transparency | No | No |
| Compression | lossy | lossy |
| Typical use | FLV is Adobe's Flash-video container carrying Sorenson Spark or H.264 streams. | MP4 pairs H.264 video with AAC audio in the ISO base media container. |
When not to convert FLV to MP4 (H.264)
- Skip MP4 for archival masters: lossy compression discards detail, so keep the FLV original.
- Keep a master copy: repeated exports stack small losses, so archive FLV before batch MP4 shares.
Limits
Starting point: FLV - FLV is Adobe's Flash-video container carrying Sorenson Spark or H.264 streams. Flash-era players are gone, so convert for current browsers. H.264 has no alpha channel, so transparency is dropped. Encode MP4 (H.264 / AAC) from FLV at a bitrate near the source, and confirm the audio track before converting.
How conversion works
Conversion runs entirely in your browser with FFmpeg WASM. Files never leave your device.
Related conversions
FAQ
How do I convert FLV to MP4 (H.264)?
Drop your FLV file onto this page, choose quality and codec settings, then click Convert. The result downloads as MP4 (H.264) instantly. All processing runs in your browser.
What codec is used for MP4 (H.264)?
The default codec for MP4 (H.264) is H.264 / AAC. You can change the video and audio codec in Advanced mode.
Does FLV to MP4 lose quality?
Slightly on re-encode; H.264 sources close to the target settings fare well.
Does FLV to MP4 fix seeking?
Usually; MP4 writes a fresh index, which repairs sparse Flash seek tables.
How do you store my files?
We do not store any processed videos. All conversion happens entirely in your browser using FFmpeg WASM.