Convert FLV to MP4
Rescue old Flash Video files now that Flash Player is gone.
Files are processed on our server in Europe. Download links expire after 60 minutes; files are then deleted automatically.
Why use Video Compressor
Private and secure
Your video is sent over an encrypted connection to our server in Europe and stored under a random ID. It is never shared with third parties or used to train AI. Download links expire after 60 minutes; files are then deleted automatically, normally within 75 minutes. Read the privacy policy
Honest results
Choose quality and resolution. Progress comes from the encoder itself, and the result shows the exact size of your MP4 next to the original.
Free, no sign-up
Video Compressor is free with no account, no watermark and no ads. It works in any modern browser on phone or desktop.
In short
FLV to MP4 converts Flash Video files, with Sorenson Spark, On2 VP6 or H.264 video, into MP4 with H.264 and AAC so they play without Flash Player. Files up to 1 GB and 30 minutes are supported.
| Accepted formats | MP4, MOV, M4V, 3GP, WebM, MKV, AVI, WMV, FLV, MPEG, MTS/TS, OGV |
|---|---|
| Maximum file size | 1.00 GB |
| Output | MP4 (H.264 video, AAC audio), max 1080p, never upscaled |
| Video limits | Up to 30 minutes, up to 4K input |
| Target size | Not on converter pages; the video compressor sets target sizes |
| Units | 1 KB = 1,000 bytes; 1 MB = 1,000,000 bytes |
| Where files are processed | On our server in Europe; not sent to third parties |
| Retention | Download link expires after 60 minutes; files deleted automatically, normally within 75 minutes |
| Price | Free, no account, no watermark |
| Typical sources | Archived Flash-era web videos, old stream recordings, early YouTube and video-sharing downloads |
| Codecs read | Sorenson Spark (H.263), On2 VP6, H.264; MP3, AAC and Nellymoser audio |
How to use it
- Choose or drop your FLV file (up to 1 GB, 30 minutes), or import it from a link.
- Keep the High quality preset, or pick a lower resolution if you also want a smaller file.
- Select Convert to MP4 and keep the tab open while it uploads and converts.
- Preview the MP4 and download it.
Why convert FLV to MP4?
FLV was the format behind Flash Player video. Browsers removed Flash at the end of 2020, and most media players and phones don't open FLV files. MP4 keeps those videos watchable on any device.
Low-resolution originals
Many FLV files are 240p to 480p. The MP4 keeps the original resolution; we never upscale, because enlarging adds file size without adding detail.
Questions
Is FLV to MP4 conversion lossless?
No. The video is re-encoded to H.264, which is lossy, but converter pages start at the High quality preset, where the difference is hard to see at normal viewing size. The picture is never upscaled, and the shorter side is capped at 1080 pixels.
Can I convert F4V files?
Yes. F4V is MP4-based, so it is detected as MP4 video and converted the same way.
What happens to my file after conversion?
It's stored under a random ID on our server in Europe. The download link expires after 60 minutes and the file is then deleted automatically, normally within 75 minutes. Canceling deletes it immediately.
Convert other formats to MP4
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Last reviewed October 31, 2026.