Convert FLV to MP4 Online Free
Convert FLV video to MP4 format with high-quality encoding. Powered by FFmpeg for reliable transcoding of any resolution.
ChangeThisFile converts your legacy Flash Video to the modern MP4 format using FFmpeg on our secure servers. Since browsers no longer support FLV playback, MP4 ensures your video works everywhere. Upload, convert, and download in seconds with automatic file cleanup, completely free.
Convert FLV to MP4
Drop your FLV file here to convert it instantly
Drag & drop your .flv file here, or click to browse
Convert to MP4 instantly
FLV vs MP4: Format Comparison
Key differences between the two formats
| Feature | FLV | MP4 |
|---|---|---|
| Video codec | H.264/VP6/Sorenson Spark | H.264/H.265 |
| Container | Flash Video | MPEG-4 Part 14 |
| Compression | Lossy | Lossy |
| Audio codec | MP3/AAC/Speex | AAC |
| Streaming | RTMP streaming | Yes (progressive + adaptive) |
| Browser support | None (Flash deprecated) | Universal |
| Max resolution | 1080p typical | 8K |
| Metadata | Basic (onMetaData) | Extensive (atoms/boxes) |
When to Convert
Common scenarios where this conversion is useful
Device compatibility
Convert FLV to MP4 for playback on devices or software that does not support FLV natively.
Cross-platform sharing
Share MP4 files with collaborators who use different operating systems or media players.
Video editing preparation
Convert to MP4 as required by your video editing software's import format requirements.
File size optimization
Re-encode FLV as MP4 to potentially reduce file size while maintaining acceptable quality.
How to Convert FLV to MP4
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1
Upload your FLV file
Drag and drop your .flv file onto the converter, or click to browse. Files up to 50 MB are supported for free.
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2
Server-side conversion
Your file is securely uploaded and converted on our servers using FFmpeg, the industry-standard multimedia framework. This typically takes a few seconds.
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3
Download the result
Once conversion is complete, click Download to save your .mp4 file. The uploaded file is automatically deleted from our servers.
Frequently Asked Questions
Yes, completely free. Convert FLV to MP4 with no cost, no signup, and no watermarks.
No. Files are automatically deleted immediately after conversion. Nothing is stored or retained.
Yes. Files are transferred over encrypted HTTPS connections. Your data is protected in transit.
The conversion uses FFmpeg, the industry-standard multimedia framework on our servers, ensuring reliable and high-quality output.
Some quality loss occurs during transcoding between formats. The converter uses high-quality encoding settings to minimize this.
Embedded subtitle tracks may not transfer between all container formats. Hardcoded subtitles (burned into video) are always preserved.
Yes. The audio track is transcoded and included in the output MP4 file.
The converter uses the standard codec for MP4: H.264/H.265.
Yes. The converter handles video of any resolution, including 4K and higher. Processing time increases with resolution.
Conversion time depends on file size and duration. Most files under 50 MB convert in seconds.
Currently, files are converted one at a time. Upload your next file after downloading the result.
Files up to 50 MB are supported for free conversion.
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