What happens when you convert MOV to FLV
- The video is re-encoded to H.264 video with AAC audio.
- Re-encoding in a browser is slow: expect several times the video's length for HD footage on a laptop, and longer on a phone. Short and low-resolution clips finish much sooner.
How to convert MOV to FLV online
- Press "Choose MOV files" and select one or more files, or drag them onto the box. You can add files of any size your device can hold in memory.
- Adjust the settings if you need to: resolution and quality control the size of the result. The defaults suit most people.
- Press "Convert to FLV". The first audio or video conversion downloads the converter engine, about 32 MB, which your browser then keeps for next time.
- Save each FLV with its download button. Close the tab and every trace of the files is gone from memory.
Why convert MOV to FLV?
MOV files usually come from iPhone recordings, Final Cut Pro and screen recordings on Mac. People convert them to FLV because FLV is still requested by a few legacy streaming and e-learning systems.
In short, MOV is good at what it was made for, and FLV is the more practical choice when the file has to play, upload or edit somewhere else. MOV plays in Safari; Chrome plays most MOV files that use H.264, while FLV does not play in browsers since Flash ended in 2020; plays in VLC.
How to convert MOV to FLV on Windows, Mac, iPhone and Android
On Windows
Open this page in Chrome, Edge or Firefox, drag your MOV files in from File Explorer, and press Convert. Each FLV is saved to your Downloads folder. If you prefer a desktop program, VLC can also convert MOV to FLV: choose Media, then Convert / Save.
On a Mac
Safari, Chrome and Firefox all work. Drag the MOV files from Finder onto the drop zone and the FLV files land in Downloads.
On iPhone and iPad
Open the page in Safari and tap Choose MOV files. You can pick from Photos or from the Files app. The converted FLV appears in Files, in the Downloads folder; to put it in your photo library, open it there, tap Share and choose Save Video. To stop the iPhone creating MOV files in future, go to Settings, Camera, Formats and choose Most Compatible.
On Android
Open the page in Chrome, tap Choose MOV files and pick them from Files or your gallery. The FLV is saved to the Download folder, where any file manager can find it. Keep the screen on while a long video converts, because Android may pause a tab in the background.
Best settings for MOV to FLV
FLV is written as H.264 video with AAC audio. The Resolution setting is the one to reach for: 1080p keeps full HD detail, 720p is plenty for phones and laptops and roughly halves the size, and 480p suits email and old devices.
The quality levels map to the H.264 CRF scale where the target uses H.264, and to fixed high-quality settings for older codecs such as MPEG-2, MPEG-4 Part 2, WMV and Theora. Re-encoding always costs a little detail, so convert from the best copy of the MOV you have.
MOV vs FLV: the differences
| MOV | FLV | |
|---|---|---|
| Full name | QuickTime movie | Flash Video |
| Type | video | video |
| Created by | Apple | Adobe (originally Macromedia) |
| First released | 1991 | 2003 |
| Compression | Lossy | Lossy |
| Usually contains | H.264, HEVC or ProRes video with AAC audio | Sorenson Spark, VP6 or H.264 video with MP3 or AAC audio |
| In a browser | plays in Safari; Chrome plays most MOV files that use H.264 | does not play in browsers since Flash ended in 2020; plays in VLC |
| Common uses | iPhone recordings, Final Cut Pro and screen recordings on Mac | old YouTube downloads and Flash-era video sites |
| MIME type | video/quicktime | video/x-flv |
About MOV and FLV files
What is a MOV file?
MOV is the QuickTime container that MP4 was based on, so the two are close relatives. iPhones record MOV, and newer iPhones use HEVC inside it, which Windows and many websites cannot play.
What is an FLV file?
FLV powered YouTube and most web video until about 2010. Since browsers dropped Flash at the end of 2020, FLV files need converting or a desktop player.
MOV to FLV not working? Common problems
- The conversion is slow. Audio and container changes take seconds, but re-encoding video runs on your own processor. Lower the resolution to 720p, close other tabs, and keep the device plugged in.
- The tab stops or reloads on a very large file. Browsers limit how much memory one tab can use, around 2 GB and less on phones. Split long recordings or convert them on a computer.
- The FLV will not play on an old device. Try the other formats offered for MOV, or choose 720p, which older players handle more reliably.
Convert MOV to FLV with ffmpeg
This converter runs ffmpeg inside your browser. If you would rather use the ffmpeg command line on your own computer, this command produces an equivalent FLV with the same kind of settings:
ffmpeg -i input.mov -c:v libx264 -crf 23 -c:a aac -ar 44100 output.flvReplace input.mov with the name of your file. For a whole folder of MOV files, run the command in a loop, or drop them all on the converter above, which processes them one after another.
MOV to FLV converter FAQ
Will I lose quality converting MOV to FLV?
A little. Both formats are lossy, so re-encoding compounds the loss slightly. Keep the default quality or higher and the difference is rarely noticeable.
Why is the FLV a different size from the MOV?
It depends on the settings. At the defaults, the FLV usually comes out close in size to the MOV; lower the quality for a smaller file.
Are my MOV files uploaded anywhere?
No. The conversion runs inside this browser tab using ffmpeg compiled to WebAssembly, so your files stay on your device. You can disconnect from the internet after the page and converter engine have loaded and it still works.
Can I convert several MOV files to FLV at once?
Yes. Select or drop as many files as you like; they are converted one after another and each gets its own download button.
How do I open an FLV file?
FLV does not play in browsers since Flash ended in 2020; plays in VLC. FLV is common for old YouTube downloads and Flash-era video sites.
Is this MOV to FLV converter free?
Yes. There is no sign-up, no watermark and no limit on how many files you convert. The site is paid for by advertising, and because conversions run on your device there is no server cost per file.
Can I convert MOV to FLV on my phone?
Yes. The converter works in Safari on iPhone and iPad and in Chrome on Android. Long HD videos convert more slowly on a phone than on a computer.