AVI to FLV Converter
Some legacy systems and archived web applications still depend on FLV format for video playback. Converting AVI to FLV allows you to provide video content for Flash-based platforms, older CMS systems, and specialized applications that were built around the Flash video ecosystem.
FLV can use H.264 for comparable quality to modern formats, or older codecs like VP6 and Sorenson Spark with reduced quality. Only convert to FLV when a specific legacy system requires it, as the format is obsolete.
How to Convert AVI to FLV
- 1
Select your AVI file from your device or drag it into the upload area.
- 2
Choose FLV as the target output format.
- 3
Click Convert and download your FLV file when ready.
AVI vs FLV — Format Comparison
| Feature | AVI | FLV |
|---|---|---|
| Full Name | Audio Video Interleave | Flash Video |
| Type | Video | Video |
| Codec | DivX / Xvid / H.264 / Uncompressed | Sorenson Spark / H.264 / VP6 |
| Lossless | No | No |
| Extension | .avi | .flv |
| Best For | Legacy video archives | Legacy web video archives |
AVI Strengths
- Wide compatibility with legacy systems
- Simple file structure
- Can contain uncompressed video for editing
FLV Strengths
- Very small file sizes
- Fast streaming performance
- Widely used in legacy video archives
Frequently Asked Questions
When to Convert AVI to FLV
- Providing video for legacy Flash-based web applications
- Converting AVI screen recordings for archived Flash-based training systems
- Supporting older CMS platforms that only accept FLV video uploads
- Maintaining Flash-dependent internal video distribution systems
Related Conversions
Embed This Converter on Your Website
Add a free AVI to FLV converter to your site with one line of code. No API key needed.
Get Embed CodeAbout Our AVI to FLV Converter
This converter uses FFmpeg compiled to WebAssembly (WASM) to transform your AVI files into FLV format entirely inside your web browser. When you select a file for conversion, the processing happens locally on your device. Your file is never uploaded to any server, never transmitted over the internet, and never stored anywhere outside your own computer. This privacy-first architecture makes our tool safe for confidential and sensitive content — including legal recordings, medical files, financial presentations, personal media, and any other material you would not want on a third-party server.
The conversion process works by decoding the AVI input using FFmpeg's highly optimized decoders, then encoding the output in FLV format with carefully tuned settings that balance quality and file size. When possible, the tool uses stream copy mode to remux (rewrap) compatible streams without re-encoding, which preserves the original quality with zero generational loss. When re-encoding is necessary due to codec differences between the two formats, the converter uses high-quality encoding settings to minimize any visible or audible quality reduction.
Supported input formats include MP4, MOV, AVI, MKV, and WebM for video, with automatic detection of the codecs and parameters inside your source file. The output is optimized for maximum compatibility with modern devices and platforms including Windows, macOS, Linux, iOS, Android, smart TVs, and all major web browsers.
Why browser-based conversion is safer: traditional online converters require you to upload your file to a remote server, where it is processed by third-party infrastructure and then made available for download. This workflow exposes your data to interception during upload, unauthorized access on the server, unclear data retention policies, and potential data breaches. Professionals in regulated industries such as healthcare (HIPAA), legal (attorney-client privilege), and finance (SOX, GDPR) often cannot use server-based converters without violating compliance requirements. Our WebAssembly-powered approach eliminates all of these risks by ensuring your data never leaves the browser sandbox on your own device.
The tool handles files up to 500 MB on desktop browsers and 200 MB on mobile devices. No account registration, no software installation, and no recurring subscription is required. Conversion typically completes in seconds for small files and a few minutes for larger ones, depending on your device's processing capabilities. Once the conversion is finished, you can download the result immediately and the source data is discarded from browser memory.