Step 1: Supply your FLV files using the button above or by haul and lay.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Get your converted MP4 files.
FLV to MP4 Conversion FAQ
What does the FLV to MP4 converter do?
+
FLV is a legacy container, often poorly supported on modern devices. Converting to MP4 rewraps the video with a current codec (H.264 / H.265 / VP9) for broad browser, phone, and TV compatibility.
Will resolution and frame rate be preserved in the MP4?
+
Yes. FLV → MP4 keeps resolution, frame rate, and aspect ratio unchanged by default. To change them, use the Resize or Speed tool on the result.
Can I add selectable subtitles once the file is MP4?
+
Yes. FLV has no usable soft-subtitle track, so subtitles for FLV content had to be burned into the picture or shipped as a separate sidecar file. MP4 carries subtitles as their own selectable stream, so after conversion you can attach an SRT track the viewer can switch on, switch off or restyle. Almost every MP4 in the wild is H.264 video with AAC audio; the container also legally holds HEVC, AV1 and VP9.
Will the MP4 play on a phone without anything installed?
+
That is the whole argument for it. MP4 is what phones record to and what every phone, tablet, console, television and browser built in the last decade decodes in hardware, so a file in it opens on whatever the recipient happens to own. Hardware decoding is the part people underestimate: it is why an hour of video plays on a phone without draining the battery, and why nothing else is a safer choice when you do not know what the file will land on. MP4 is the safest possible delivery target — every phone, browser, console, editor and Smart TV built in the last decade plays it without extra software.
Will the MP4 play in a browser when the FLV would not?
+
Yes, and that is usually the whole reason for the conversion. An FLV embedded in a web page either shows a broken player or forces a download, because browsers ship no decoder for it. MP4 plays inline through the native HTML5 video element with no plugin and no external application.
Is it worth converting old FLV recordings to MP4 at all?
+
For anything you intend to keep, yes. FLV belongs to an earlier generation of video tooling and the software that reads it is steadily disappearing from phones, browsers and operating systems. Moving the footage to MP4 now, while a clean decoder still exists, is the difference between an archive you can open in ten years and one you cannot. No current browser, phone or TV can play FLV — anything still in this container has to be moved out of it to remain watchable.
Is there a file-size limit when converting FLV to MP4?
+
Free conversions have a size limit per file, set by the type of file, and the page tells you when a file is over it. A paid plan removes that limit, so much larger files can be converted.
Can I batch-convert several FLV files to MP4 at once?
+
Several files in one job need a paid plan. Free use is one file per conversion, one conversion an hour. On a paid plan you can add several files to one job, then download each result on its own or all of them in one ZIP.
What happens to my FLV files after the conversion?
+
Uploaded files are processed on our own conversion servers, nobody looks at them, and they are not shared. The upload and the converted file are both deleted automatically about 24 hours after the conversion, which leaves time to download the result. See /privacy/ for the full policy.
Will my MP4 play on phones, tablets, and TVs?
+
Yes — MP4 uses modern codecs that play natively on iOS, Android, Smart TVs, game consoles, and every modern browser.
Do I need to install software to convert FLV to MP4?
+
No. The converter runs entirely in your browser plus our cloud — no plugin, no install, no admin rights. It works on Windows, macOS, Linux, ChromeOS, iOS, and Android.
Do I need an account to convert FLV to MP4?
+
Yes. One conversion an hour is free, with no account needed, for a file within the free size limit. A paid plan removes the hourly limit and the size limit, and lets you add several files to one job.
