Convert MP4 to FLV

Transform your universal video format for web and devices into FLV format. Free, private, and browser-based.

How it works

  1. Upload MP4 Files — Drag and drop your MP4 files into the converter, or click to browse. Common sources: smartphones, screen recordings.
  2. Convert to FLV — The converter processes your files to FLV format entirely in your browser. No files are uploaded to any server — your privacy is guaranteed.
  3. Download Results — Download your converted FLV files instantly. For multiple files, download individually or as a ZIP archive.

Why convert MP4 to FLV

  • Leverage FLV advantages: small file sizes
  • Overcome MP4 limitations: lossy compression — some quality loss
  • Upload to websites and platforms that require or prefer FLV format
  • FLV is widely supported across image editors, media players, and operating systems

FAQ

Is MP4 to FLV conversion free?
Yes, Fileza.io converts MP4 to FLV completely free with no limits on file size or number of conversions. No hidden fees, no watermarks, and no account required.

Will I lose quality converting MP4 to FLV?
Both MP4 and FLV use lossy compression. Output quality is excellent at high quality settings (85%+) — most people cannot see any difference.

Is it safe to convert MP4 to FLV online?
Absolutely. Unlike most online converters, Fileza.io processes your files entirely in your browser using WebAssembly. Your MP4 files are never uploaded to any server — the conversion runs on your own device, keeping your files 100% private.

Can I convert multiple MP4 files to FLV at once?
Yes, Fileza.io supports batch conversion. Drag and drop multiple MP4 files at once and they will all be converted to FLV simultaneously. Download them individually or as a ZIP archive.

Does MP4 to FLV conversion work on mobile?
Yes, the converter works on any device with a modern web browser — iPhones, iPads, Android phones, and tablets. No app installation required.

Will the converted FLV files be smaller or larger than MP4?
FLV files are generally smaller than MP4 files. The exact reduction depends on your quality settings and the content of your files.

How long does MP4 to FLV conversion take?
Most conversions complete in seconds. The exact time depends on file size and your device performance. Since processing happens locally in your browser, faster devices convert more quickly. Video files may take longer due to re-encoding.