1. Upload your MP4 file
Start by dragging and dropping your MP4 file into the upload area, or click to browse your device and select your file in the list.
MP4 to FLV Converter Online
Convert your MP4 (.mp4) file to FLV (.flv) in seconds straight from your browser. No installs. No watermarks. 100 % free.
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Why choose HappyScribe?
47+ Formats
Convert from MP4 to FLV but also 47+ other formats.
100% Free
No signups, no fees, no hidden restrictions. Convert MP4 to FLV directly in your browser for free.
Secure
We take your security seriously. All file transfers use 256-bit SSL encryption.
Online
No installs needed; convert MP4 to FLV right from your browser, on any device, anytime.
How to convert MP4 to FLV?
2. Choose FLV format
Next, pick FLV as the format you’d like to convert your video into. Alternatively, we support +47 formats that you can choose from. When you’re ready, hit the Convert button.
3. Download your converted FLV
Once the conversion is complete, you’ll get a download link right away. Just click to save the file to your device. It’s fast, easy, and doesn’t require any software installation.
What is a MP4 file?
MP4 (MPEG‑4 Part 14) is the dominant container for online video. Based on QuickTime atoms, it can hold H.264/AVC, HEVC, AV1, AAC, AC‑3, timed text, and fragmented segments for adaptive streaming. Finalised in 2001 and revised in 2003 (ISO/IEC 14496‑14), MP4 became the hand‑off format of choice thanks to the iPod Video and PlayStation Portable. The arrival of HLS and DASH further entrenched MP4, which supports ‘moov’ boxes at either head or tail for progressive download or live streams.
What is a FLV file?
Flash Video (FLV) is a container that encapsulates Sorenson Spark, VP6, or H.264 video together with MP3/AAC audio and on‑screen data events for ActionScript. It became the backbone of early YouTube and news portals because the small header footprint yields quick progressive playback. Macromedia introduced FLV in 2002 with Flash Player 6, offering the first ubiquitous plug‑in‑based video experience on the Web. After Adobe’s acquisition, FLV evolved to support H.264 in 2007 but began losing ground once HTML5 <video> gained traction. By the end of 2020, Adobe disabled Flash, and most CDNs convert FLV archives to MP4 or HLS.
Free Online MP4 to FLV Converter
Need to convert your audio file from MP4 to FLV? It’s simple. Just upload your file, choose the output format, and click ‘Convert’. That’s it — no downloads, no complicated software, and no hidden costs. Our tool is designed to be fast, secure, and completely free, so you can turn your files into the format you need in seconds.
Whether you’re converting audio for sharing, editing, or playback on different devices, our converter ensures high-quality output every time. After your conversion, you’ll also have the option to transcribe video to text, making it easy to turn your FLV files into accurate, editable text in just a few clicks.
Frequently Asked Questions
How to open a MP4 file?
Virtually every player from Safari and Chrome to Xbox and Roku handles MP4. When editing, DaVinci Resolve and Final Cut Pro will optimise H.264 to intraframe proxies for smoother scrubbing. HandBrake transcodes old codecs like DivX to modern H.264+AAC MP4 profiles.
How to open a FLV file?
Desktop apps like VLC or MPC‑HC open FLV seamlessly. If you encounter a Spark‑encoded clip, convert using FFmpeg: `ffmpeg ‑i input.flv ‑c:v h264 output.mp4`. Web players no longer stream FLV, so upload sites recommend remuxing to MP4 or WebM.
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