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FLV to MP4 Converter

FreeNo uploadNo watermarkBatch support
FLV MP4
100% private — files never leave your device

Convert to MP4 when a video must play everywhere — it is the one format you never have to worry about. If your files are still in FLV format, this page is the shortcut: FLV is the Flash-era video container from thousands of old video sites and screen recordings. Modern players have dropped it.

iLoveConverter processes everything locally on your computer, which makes it private and fast: no upload wait, no server storage, no limits. Add as many files as you like — batch conversion is built in.

How FLV compares to MP4

FLV MP4
Compression VP6 / H.264 legacy H.264 / HEVC / AV1 + AAC
Quality Of its era Depends on encode settings
Compatibility Legacy players only Plays everywhere
Best for Early web video archives Distribution, web, storage

How to convert FLV to MP4

  1. 1

    Select your files

    Drag & drop your FLV files onto the area above, or click to browse. You can add multiple files at once for batch conversion.

  2. 2

    Convert instantly

    Click "Convert to MP4". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.

  3. 3

    Download results

    Download each converted MP4 file individually, or grab everything at once as a ZIP archive.

About the FLV format

FLV (Flash Video) was the video format of the early streaming web — YouTube's original delivery container from 2005 to ~2010, played by Adobe Flash Player. Later versions carried H.264/AAC, but the container lived and died with Flash, which reached end-of-life in 2020.

Modern browsers cannot play FLV at all, and only niche players (VLC) bother. If you have an FLV archive, converting to MP4 recovers the same H.264 video into a container every device accepts.

+ Strengths

  • ✓Only relevant for early-web video archives

! Limitations

  • −Dead ecosystem — Flash ended in 2020
  • −No browser support at all

About the MP4 format

MP4 (MPEG-4 Part 14) is the universal delivery container of digital video. It wraps H.264, HEVC or AV1 video with AAC audio, and its structure — separate metadata (moov) and media atoms — is what makes streaming, seeking and fast-start playback possible. Phones, cameras, TVs, browsers and every social platform assume MP4 first.

Quality is entirely a function of the codec and bitrate chosen at encode time, so an MP4 can be a 10 Mbps HEVC master or a postage stamp. That flexibility plus total playback coverage is why nothing has displaced it in twenty years — conversion between formats almost always ends in MP4.

+ Strengths

  • ✓Plays on every device and platform in existence
  • ✓Streaming-ready structure (fast start, seeking)
  • ✓Choice of modern codecs: H.264, HEVC, AV1

! Limitations

  • −Quality depends entirely on encode settings
  • −HEVC variants hit licensing gaps on some platforms

Why convert FLV to MP4?

Think of it as moving your file to the container that fits the job. Dead ecosystem — Flash ended in 2020 MP4 works differently: Plays on every device and platform in existence If any of that sounds like your task, run the conversion — it takes seconds and nothing leaves your device.

Frequently asked questions

Is this FLV to MP4 converter really free?

Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.

Are my files uploaded to a server?

No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.

Does it work on Windows, Mac, iPhone and Android?

Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.

Is there a file size limit for FLV to MP4?

The only limit is your device's memory, since nothing is uploaded. Files up to a few hundred megabytes work fine on a modern desktop browser; very large files simply take a little longer.

Does converting FLV to MP4 re-encode my video?

Yes. The video is decoded and re-encoded with the settings chosen by the quality slider, which is what allows the format and size to change. For an archival copy, keep higher quality; for sharing, lower quality gives a much smaller file.

Will the audio track be kept?

Yes. The audio is carried over and re-encoded to the standard audio codec of MP4, staying in sync with the video. If your FLV file has multiple audio tracks, the first one is used.

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