FLV to MP4 converter
Convert FLV to MP4 free online. Rescue old Flash videos for modern browsers, phones, and archives. No signup, 500 MB, files deleted in 1 hour.
Drop a file to convert here
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About MPEG-4 Video Format
Common Use Cases
- Converting Flash video archives to modern format
- Enabling playback without Flash plugin
- Preserving old streaming video content
FLV (Flash Video) was the container format that powered web video through most of the 2000s, and if you have an old archive of YouTube downloads, screen recordings, or streaming captures from that era, they are probably FLV files. Flash itself was retired by Adobe in 2020 and removed from every modern browser, which means FLV files no longer play anywhere without a dedicated legacy player. Converting to MP4 brings them back into the land of the living.
FLV is a dead web-video container tied to Adobe Flash, while MP4 is the modern universal standard, so the conversion is essentially a rescue operation that makes old Flash content playable on current devices and browsers.
Why Convert FLV to MP4?
Play without Flash, which no longer exists
Adobe officially killed Flash at the end of 2020, and every major browser has removed Flash support entirely. FLV files that used to play in YouTube or a web player simply cannot open in any modern browser. Converting to MP4 gives your archive a second life with a format every current device understands.
Better compression on most old content
FLV typically carried Sorenson Spark, VP6, or early H.263 video, which are all far less efficient than modern H.264. Re-encoding into an H.264 MP4 usually delivers a smaller file at the same perceptual quality, which is useful when you are digitizing a big pile of old clips for storage.
Play on phones, tablets, and smart TVs
No mobile device has ever played FLV natively, and smart TVs never supported it either. MP4 plays everywhere, so converting an FLV archive unlocks your old content for iPhone, iPad, Android, Chromecast, Fire TV, Apple TV, and anything else that touches video in the current decade.
Import into modern editors
Premiere Pro, Final Cut, iMovie, and DaVinci Resolve do not reliably accept FLV anymore. If you want to remix, trim, or excerpt a piece of old Flash video, converting to MP4 first is the only realistic way to get it into a timeline.
When to use each
Use FLV when...
- Opening archived files in a Flash-era player
- Running a legacy internal tool from the 2000s
- Inspecting old web-video captures for reference
- Almost never in 2026 honestly
- Preserving an untouched original for archival
Use MP4 when...
- Playing on any modern phone or tablet
- Uploading to YouTube, Vimeo, or social media
- Editing in Premiere, Final Cut, or iMovie
- Sharing via iMessage, AirDrop, or email
- Streaming to smart TVs and game consoles
Common use cases
- Converting Flash video archives to modern format
- Enabling playback without Flash plugin
- Preserving old streaming video content
How to use
- Upload your FLV file. Drag and drop your FLV onto the upload area, or click to browse for a file. The upload limit is 500 MB per file, which comfortably covers old low-bitrate Flash videos since they were almost always small to begin with.
- Start the conversion. Click Convert File and our servers re-encode the video with FFmpeg. The old Sorenson, VP6, or H.263 stream is transcoded into H.264, audio is converted to AAC, and the result is wrapped in a standard MP4 container.
- Download your MP4 file. A download link appears when processing finishes. Save the MP4 and it plays immediately on any modern device. Uploaded files and converted output are automatically deleted within 1 hour.
Frequently asked questions
- Why will my FLV not play in Chrome or Firefox anymore?
- FLV was tied to Adobe Flash, and Flash was officially discontinued and removed from every major browser at the end of 2020. There is no path to play FLV files directly in a browser today. Converting to MP4 is the fix because MP4 plays natively in HTML5 video without any plugin.
- Will conversion improve the quality?
- No, it cannot. Quality is capped by the original FLV encode, which was almost always aggressively compressed for slow connections. A good conversion preserves the existing quality cleanly and does not add new artifacts, but there is no way to recover detail that was never in the source.
- Will the MP4 be larger or smaller than the original FLV?
- In most cases the MP4 is similar in size or slightly smaller. H.264 is much more efficient than the codecs typically found in FLV, so at the same visual quality the output is usually smaller. Really low-bitrate FLV sources may come out roughly the same size to preserve the existing quality.
- Is there a file size limit?
- Yes, 500 MB per file. Old FLV videos are almost always well under that limit, so most uploads go through without trouble. If you somehow have a larger FLV, trim it first before uploading.
- Is FLV to MP4 conversion free?
- Yes. Free anonymous use is available with a daily cap, registered FileFactory accounts get a higher daily allowance, and Premium or Lifetime members enjoy unlimited conversions.
- How long do you keep my uploaded files?
- Uploaded FLV files and converted MP4 output are automatically deleted within 1 hour. Transfers use encrypted connections and your files are never shared with third parties.
- Do I need Flash Player to convert FLV to MP4?
- No. The conversion happens on our servers using FFmpeg, which reads FLV files directly without any Flash runtime. You do not need Flash installed on your machine, which is good because you cannot install it anymore.