🎬 Video Converter

Convert FLV to AVI — Free & Private

FLV (Flash Video) files are digital fossils from the web's Flash era — YouTube used the format until around 2012, and countless learning platforms, news sites, and video archives stored content in FLV. Adobe ended Flash Player on 31 December 2020, making FLV files permanently unplayable in any modern browser without conversion. Downloaded web video, archived course content, and early streaming captures are the most common sources. Converting to AVI provides compatibility with legacy Windows video editing software, older hardware players, and industrial systems that require the AVI container specifically.

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How to convert FLV to AVI free: open the Convertlo FLV to AVI converter, drop your FLV file, and download the AVI. Powered by FFmpeg.wasm in your browser — no install required, completely free.

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How to Convert FLV to AVI

Open the Converter

Click "Convert Now" to open with FLV → AVI pre-selected.

Upload Your FLV

Drag & drop your FLV file or click Browse.

Convert Instantly

FFmpeg.wasm processes your video locally — nothing uploaded.

Download AVI

Your converted AVI file downloads automatically.

Why Convert FLV to AVI?

📼 From FLV — modernise legacy Flash video files to formats supported on all current devices
🖥️ Windows-native — plays in Windows Media Player without extra codecs
🔄 Legacy compatible — supported by older software and set-top boxes
🎬 Wide editor support — opens in virtually every video editor
📺 Broad device support — plays on most TVs and media centres
🔒 100% private — files never leave your device

FLV vs AVI — Format Comparison

Feature	FLV	AVI (output)
Full name	Flash Video	Audio Video Interleave
Creator	Adobe / Macromedia	Microsoft
Codec	H.263 / H.264 (VP6)	DivX / XviD / DV (legacy)
Container	FLV (.flv)	AVI (RIFF)
Browser support	❌ No support (Flash EOL Dec 2020)	❌ No browser support
Royalties	Proprietary (Adobe)	Proprietary
File size	Medium	Large — older compression codecs
Best for	Legacy Flash-era web video only	Legacy DV camcorder footage, 2000s video

Features

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100% Private

Files never leave your browser.

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Instant

In-browser processing, no waiting.

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Free

No account, no fee, no watermarks.

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Quality Preserved

High-quality settings by default.

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Mobile-Friendly

Works on any device.

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No Install

Works in any modern browser.

Key Questions About FLV to AVI, Answered

Direct answers structured for AI extraction, voice search, and featured snippets.

Will my video be re-encoded or just remuxed when converting FLV to AVI?

It depends on which era of FLV you have. Flash Video from roughly 2008 onward usually carries H.264 video, while older FLV files use VP6 or Sorenson H.263. AVI doesn't have reliable, universal support for H.264 the way MP4 or MKV do, so Convertlo re-encodes the video into an AVI-friendly codec regardless of what the FLV originally contained — this avoids producing an AVI file that some players refuse to open.

H.264 FLV and VP6/Sorenson FLV are both re-encoded for AVI output
AVI is itself a legacy container — only convert to it if older software specifically requires it
If you don't need AVI specifically, MP4 or MKV preserve quality better and remux more often

Will the output AVI play in VLC and older Windows software?

Yes — that's the main reason to choose AVI today. VLC and most legacy Windows applications (old editing suites, embedded systems, industrial software) still expect AVI files. Outside of that niche, AVI has weaker support than MP4 on phones, browsers, and streaming platforms.

VLC and older Windows tools: open AVI without issue
Phones, browsers, social platforms: prefer or require MP4
Choose AVI only when a specific legacy program or device requires it

How much will the file size change going from FLV to AVI?

Expect the file to grow somewhat. AVI's codec options compress less efficiently than the H.264 typically found in newer FLV files, so the AVI output is often a bit larger than the source FLV at the same visual quality.

H.264 FLV → AVI: usually larger after re-encoding to an AVI-compatible codec
VP6/Sorenson FLV → AVI: size change varies more, depending on the original bitrate
If file size matters more than legacy compatibility, MP4 or MKV keep the original H.264 efficiency

Why does my old FLV file stop playing on modern devices?

Adobe Flash Player — the only widely-installed software that played FLV directly — was permanently discontinued on December 31, 2020. Browsers removed the Flash plugin entirely, and no phone, smart TV, or modern app ever added native FLV support.

No browser has played FLV natively since Flash Player's 2020 retirement
iOS and Android have never supported FLV playback
Converting to MP4 is usually the better long-term fix unless you specifically need AVI for legacy software

Go Deeper: FLV to AVI Resources

In-depth articles to help you understand the formats, pick the right settings, and get the best results.

📖FLV to MP4: Rescue Your Old Flash Videos 📖Video Format Guide: MP4, MKV, AVI, MOV & More

Frequently Asked Questions

Adobe killed Flash Player in December 2020, so FLV files from that era need converting — AVI is a long-standing, universally playable container that revives them on today's PCs.

No — FFmpeg.wasm decodes the FLV's H.263/VP6/H.264 stream and rebuilds it as an AVI file entirely on your own device.

Some re-encoding is involved since AVI typically expects Xvid/DivX-style streams rather than FLV's web-era codecs, so minor quality shifts are normal.

Rarely — FLV was built for web streaming, so most FLV files are quite small and convert to AVI almost instantly.

Because FLV files from the streaming era are typically compact, this conversion is usually one of the fastest on the site.

FLV files often use H.264 or older Sorenson Spark/VP6 codecs. Converting to AVI re-encodes the video, which introduces some quality loss. If the FLV uses H.264, converting to MP4 (instead of AVI) is more efficient as it may avoid re-encoding — the H.264 stream can be remuxed directly.

AVI (Audio Video Interleave) was introduced by Microsoft in 1992 and is considered a legacy format. It doesn't support streaming, has limited codec flexibility compared to MKV or MP4, and doesn't handle modern codecs (H.265, AV1) well. It remains in use for compatibility with older editing software and hardware that doesn't accept MP4.

Technically yes — AVI can contain HD or 4K content if the codec supports it. In practice, AVI files use older codecs (DivX, Xvid, MPEG-4 Part 2) that don't handle high resolutions efficiently. For HD or 4K video, MKV or MP4 with H.264/H.265 are better containers.