Convert MP4 to FLV Online Free
Convert MP4 to FLV (Flash Video) for compatibility with legacy systems, older web video players, or applications that still use Flash-based video playback.
By ChangeThisFile Team · Last updated: March 2026
ChangeThisFile converts your MP4 video to Flash Video format using FFmpeg on our secure servers. Though FLV is a legacy format, some older streaming platforms and media workflows still require it. Files are auto-deleted after conversion, free to use with no signup needed.
Convert MP4 to FLV
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Drag & drop your .mp4 file here, or click to browse
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MP4 vs FLV: Format Comparison
Key differences between the two formats
| Feature | MP4 | FLV |
|---|---|---|
| Technology | Modern MPEG-4 standard | Adobe Flash Video (legacy) |
| Codec | H.264, H.265 | H.263 or H.264 (Sorenson Spark) |
| Browser support | Universal native support | Requires Flash plugin (discontinued) |
| Streaming | HLS, DASH streaming | RTMP streaming (legacy) |
| File size | Efficient | Larger for equivalent quality |
| Use case | Modern web and devices | Legacy Flash systems only |
| Metadata | Rich metadata | Basic FLV metadata |
When to Convert
Common scenarios where this conversion is useful
Legacy LMS and e-learning platforms
Older Learning Management Systems (LMS) built before 2015 may only support FLV video. Convert MP4 course content to FLV for compatibility with legacy e-learning software.
Archived website video restoration
Web archives and historical websites often used FLV for video. Convert existing MP4 content to FLV to recreate or archive original video experiences for historical purposes.
Legacy kiosk and POS systems
Some retail kiosk and point-of-sale systems with embedded browsers use legacy Flash video playback. FLV conversion ensures compatibility with these embedded systems.
Internal legacy corporate systems
Corporate intranets with embedded Flash video players may require FLV format. Convert MP4 training or presentation videos for playback on these internal systems.
Who Uses This Conversion
Tailored guidance for different workflows
Content Creators
- Convert MP4 footage to FLV for uploading to YouTube, TikTok, or social media platforms
- Transform MP4 screen recordings to FLV for sharing in blog posts or tutorials
Video Editors
- Convert MP4 raw footage to FLV for importing into editing software like Premiere or DaVinci Resolve
- Transform MP4 project exports to FLV for client delivery or final distribution
Social Media Managers
- Convert MP4 brand videos to FLV to meet platform-specific format requirements
- Transform MP4 ad creatives to FLV for cross-platform publishing campaigns
How to Convert MP4 to FLV
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1
Upload your MP4 file
Drag and drop your .mp4 file onto the converter, or click to browse. Files up to 500MB are supported.
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2
Server-side conversion
Your file is securely uploaded and re-encoded using FFmpeg into FLV format. Processing typically takes a few seconds.
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3
Download the result
Click Download to save your converted .flv file. The original and converted files are automatically deleted from our servers.
Frequently Asked Questions
No. Adobe Flash Player was discontinued in December 2020. Modern browsers no longer support FLV playback. Use FLV only for legacy systems that require it.
Some legacy enterprise systems, older LMS platforms, archived websites, and embedded hardware were built around Flash and have not been updated. FLV is needed to feed content into these systems.
FLV typically uses older, less efficient codecs than MP4. Re-encoding involves some quality trade-off. The output uses the best settings available for FLV.
Yes. Files are transferred over HTTPS and automatically deleted from our servers after conversion.
Yes. VLC Media Player supports FLV playback on all platforms.
The FLV output uses MP3 audio, which is compatible with most Flash-era players.
Files up to 500MB are supported.
Yes, completely free. No signup or subscription required.
Yes. Use the FLV to MP4 converter on ChangeThisFile to convert in the reverse direction.
Most conversions complete in a few seconds. Longer videos may take up to a minute.
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