FLV to MP4 Converter
Convert FLV to MP4 in your browser. Free, no signup. Conversion files are not uploaded to Format Convertly servers. Learn the formats, then convert when your workflow needs MP4.
Choose a file or drag and drop
Drop your FLV file here or
Choose file · Drag & drop · Public file link
- Processed on your device
- No conversion file stored on our servers
- Maximum file size: 100 MB
Conversion runs in your browser. Files are not uploaded to Format Convertly servers.
Processed on your device
No conversion file stored on our servers
Conversion Settings
Customize the output to match your needs.
Convert Quality
92%Output
Output options for this format are applied automatically during browser conversion. Drop your file above to begin.
Advanced settings
Additional Options
Quality or bitrate forces a re-encode. Width/FPS apply only when creating GIF or animated WebP.
How to Convert FLV to MP4
Open the FLV → MP4 converter
Open the FLV to MP4 converter on Format Convertly.
Add your FLV file
Add the legacy FLV course or archive video in the browser.
Download MP4
Convert and download MP4 for modern devices.
Why Convert FLV to MP4?
Private by design
FLV → MP4 runs in your browser. Files are not uploaded to a remote conversion queue.
Ready for the next step
Convert when a site, editor, or teammate expects MP4 instead of FLV.
Practical quality
MP4: lossy (codec-dependent). Lossy targets trade size for speed — preview when it matters.
Wide compatibility
FLV is commonly used for Recovering old Flash-era recordings and Archival course videos from the 2000s–2010s.
FLV vs MP4
A quick side-by-side before you convert — deeper comparison lives on the full guide.
| Feature | FLV | MP4 |
|---|---|---|
| Kind | video container | multimedia container |
| Compression | lossy (legacy Flash codecs / H.264 in later FLV) | lossy (codec-dependent) |
| Lossy / lossless | Typically lossy | Typically lossy |
| Transparency | Not supported / N/A | Not supported / N/A |
| Best for | Recovering old Flash-era recordings; Archival course videos from the 2000s–2010s | Social uploads; Website video |
| Typical size | Varies; many old FLVs are low-resolution lecture captures | Large vs audio; efficient vs uncompressed video |
| Browser / web support | Flash is gone — convert to MP4 for HTML5 | Excellent HTML5 video support |
| Compatibility | Legacy only — modern browsers will not play FLV without conversion; VLC can open many archives before you remux to MP4 | The default video container for phones, social platforms, smart TVs, and HTML5 players — safest modern delivery choice |
Choose FLV when…
- Recovering old Flash-era recordings
- Archival course videos from the 2000s–2010s
- Migrating legacy learning libraries
- One-time modernization to MP4
Choose MP4 when…
- Social uploads
- Website video
- Phone playback
- Client delivery from editors
What happens to video quality?
MP4 compatibility: The default video container for phones, social platforms, smart TVs, and HTML5 players — safest modern delivery choice
Tip
Preview with VLC first if conversion fails — some FLVs use odd codecs.
Does FLV to MP4 reduce quality?
MP4 is typically lossy (lossy (codec-dependent)). Use a higher bitrate when fidelity matters, and keep the FLV master for archival.
MP4 format guide →Should I keep the original FLV?
Yes when you may need to re-encode later. FLV: FLV powered early YouTube-style streaming inside Flash Player. Flash is gone — convert FLV to MP4 to keep old recordings playable on modern devices.
FLV format guide →FLV · MP4
Related converters FLV
Related converters MP4
Frequently Asked Questions
More on quality loss: conversion quality guides · problem-solution guides
Does converting FLV to MP4 reduce quality?
It can — both sides are typically lossy. A careful encode may look similar; repeated re-encodes cause generational loss. Prefer converting once from the best master you have.
Can you recover quality after converting?
Not from a lossy output alone. Return to the original master (or a better source). Converting to a lossless format does not resurrect discarded detail.
What is generational loss?
Damage that stacks when you decode and lossy-encode the same file over and over (for example JPG→edit→JPG). Edit from masters and export delivery formats once.
Where can I learn more about conversion quality?
Browse Format Convertly’s Quality guides for topics like whether conversion reduces quality, JPG↔PNG myths, WebP/MP3/MP4 tradeoffs, recovery limits, and generational loss — each links to the right converter.
What is a FLV file?
FLV is Flash Video — a legacy streaming format from the Adobe Flash era. FLV powered early YouTube-style streaming inside Flash Player. Flash is gone — convert FLV to MP4 to keep old recordings playable on modern devices.
Is FLV lossy or lossless?
FLV is typically lossy (lossy (legacy Flash codecs / H.264 in later FLV)). That keeps files small but means discarded detail cannot be restored later.
What is a MP4 file?
MP4 is a ubiquitous multimedia container usually holding H.264/H.265 video and AAC audio. MP4 is the safest video delivery format for phones, web, and social platforms. Shoot or edit in whatever your camera prefers, then provide an MP4 derivative for sharing.
Is FLV to MP4 private?
Yes. The file is processed locally in your browser and is not uploaded to Format Convertly servers.
Ready to Convert Your Files?
FLV to MP4 privately in your browser.