Convert FLV to AAC Online Free

Extract the audio from your FLV Flash video and save it as AAC — the modern, universally supported audio format. Perfect for rescuing audio from obsolete Flash-era videos into a format every device plays.

Quick Answer

ChangeThisFile extracts audio from your FLV Flash video and encodes it as AAC using FFmpeg on our secure servers. AAC plays natively on iOS, Android, Windows, and all major streaming platforms — the perfect modern alternative to obsolete FLV audio. Files are auto-deleted, free with no signup needed.

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Convert FLV to AAC

Drop your FLV file here to convert it instantly

Drag & drop your .flv file here, or click to browse

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FLV vs AAC: Format Comparison

Key differences between the two formats

FeatureFLVAAC
TypeAdobe Flash video containerLossy audio bitstream (ADTS)
DeveloperAdobe SystemsMPEG / ISO standard
StatusObsolete — Flash EOL 2020Actively supported modern standard
Mobile compatibilityNot supported on smartphonesNative on iOS and Android
Audio codecMP3, AAC, Nellymoser, or PCMAdvanced Audio Coding
File sizeSmall to moderate (video included)Very small — efficient audio only
Use caseLegacy Flash web videoMobile apps, streaming, broadcast, all devices

When to Convert

Common scenarios where this conversion is useful

Convert FLV music video audio for smartphone playback

FLV files do not play on modern smartphones. Extract the audio as AAC to listen to old Flash-era music content natively on any iPhone or Android device without a specialized Flash-compatible player.

Rescue audio from FLV video archives

With Flash Player deprecated, FLV files are increasingly hard to access. Converting to AAC ensures the audio from these archives remains playable on all current devices and software for years to come.

Extract FLV audio for streaming platform upload

Streaming platforms accept AAC audio files. Convert FLV video content to AAC to upload audio from old Flash-era productions to Spotify, SoundCloud, or podcast hosting services.

Convert downloaded FLV audio for offline listening

Downloaded FLV files require special software to play. Converting the audio to AAC creates a universally compatible audio file you can add to any music player, phone, or streaming app for offline listening.

Create audio from FLV lecture or tutorial archives

Many educational websites used FLV for video delivery in the 2000s-2010s. Extract audio from FLV lecture recordings as AAC for continued accessibility on modern devices and e-learning platforms.

How to Convert FLV to AAC

  1. 1

    Upload your FLV file

    Drag and drop your .flv file onto the converter or click to browse and select it. Files up to 500MB are supported.

  2. 2

    Server-side AAC encoding

    Your FLV is uploaded over HTTPS and FFmpeg extracts and decodes the audio (MP3, AAC, Nellymoser, Speex, or PCM), encoding it as AAC. The video stream is discarded.

  3. 3

    Download your AAC file

    Click Download to save the .aac file. Both the original FLV and converted AAC are automatically deleted from our servers after download.

Frequently Asked Questions

Adobe officially ended support for Flash Player on December 31, 2020. As a result, FLV files are increasingly difficult to play without specialized tools. Converting FLV audio to AAC future-proofs your content in a universally supported format.

FLV supports MP3, AAC, PCM, Nellymoser (for voice chat), and Speex audio. Early YouTube videos used FLV with MP3 audio. Later FLV content transitioned to AAC. FFmpeg decodes all of these codecs.

AAC is a more modern and efficient codec than MP3. At the same bitrate, AAC delivers better audio quality. Converting FLV MP3 audio to AAC at a high bitrate can improve perceived quality compared to a low-bitrate FLV source.

Yes. AAC is Apple's preferred audio format and plays natively on all iOS and macOS devices without any additional apps or codecs.

FFmpeg encodes AAC at a high variable bitrate by default, typically 192 kbps VBR. This provides excellent quality for music, speech, and general audio content.

Yes. FFmpeg supports decoding Nellymoser and Speex audio from FLV containers. These will be decoded and re-encoded as standard AAC audio in the output.

Yes. ChangeThisFile is completely free. No signup, no limits, and no fees.

Yes. Android has supported AAC natively since version 1.0. AAC files play in the default media player and all major third-party apps.

Very fast — typically just seconds. Only the audio stream is processed and the video is discarded.

Yes. All uploads are HTTPS-encrypted and files are deleted from our servers immediately after conversion. We never retain or access your content.

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