Convert FLV to MP3 Online
Extract audio from Flash FLV videos. Free, in your browser, no file uploads.
.flv · up to 100 MB
What you can do
Rescue audio from the Flash era of the internet
Pre-2015 YouTube and Newgrounds
Extract audio from FLVs downloaded from YouTube, Dailymotion, and Flash-era sites from 2005–2015.
100% private
Your FLV files never leave your device. Conversion happens in your browser.
MP3, AAC, and Nellymoser
Compatible with all three audio codecs in the FLV standard: MP3, AAC, and Nellymoser.
Flash soundtracks
Extract music from Flash demos, Newgrounds animations, and viral videos from the 2000s.
How it works
Three steps, no hassle
Upload your FLV file
Drag or select the .flv downloaded from YouTube (pre-2015), Newgrounds, or any Flash-era site. No signup.
Audio extraction in the browser
The MP3, AAC, or Nellymoser audio from the FLV container is extracted and converted directly on your device.
Download your MP3
Flash game soundtrack, web video intro, or downloaded clip audio — ready in universal MP3.
FAQ
Got questions?
FLV (Flash Video) is the video container format developed by Macromedia (acquired by Adobe in 2005) and introduced with Flash Player 6 in 2002. It became the dominant web video format between 2005 and 2012 because Flash Player was installed on 98% of desktop browsers and was the only cross-platform system capable of playing video in the browser without OS-specific plugins. YouTube used FLV as its primary delivery format from its founding in 2005 until the transition to MP4 H.264 around 2010–2012 (though FLV files remained downloadable until 2015).
FLV files can contain three main audio codecs: (1) MP3 (MPEG-1 Audio Layer III, FLV codec ID: 2) — the most common in YouTube FLV and websites from 2005–2010; (2) AAC (Advanced Audio Coding, FLV codec ID: 10) — introduced in Flash Player 9 Update 3 (2007), used in higher-quality FLV and pure audio streaming; (3) Nellymoser (FLV codec IDs: 0, 5, 6) — a proprietary codec from Nellymoser Inc. used specifically for low-quality Flash audio, common in video chats, real-time audio streams, and Flash games using microphone capture.
.swf (Flash application) files are not the same as .flv (Flash video). Newgrounds game SWF files have audio embedded directly in the SWF binary, not as a separate audio stream. To extract music from SWF files, you need specific tools like SWF Investigator (Adobe), JPEXS Free Flash Decompiler, or SWFT. If you have a game video recorded as .flv (for example with screen capture software), you can extract the audio with this converter.
Yes. YouTube FLVs from the 2005–2012 era typically contain MP3 audio at 128 kbps (standard videos) or AAC at 128–256 kbps (HD 720p/1080p videos uploaded from 2009). Both MP3 and AAC inside the FLV container are fully compatible with the converter. Pre-2015 YouTube FLVs you saved to your hard drive are exactly the type of file this tool was designed for.
Nellymoser audio (Nellymoser ASAO Codec) is a proprietary codec from Nellymoser Inc. developed specifically for real-time voice communications over low-latency connections. It operates at 5–20 kbps and its quality is comparable to AMR-NB: acceptable for voice, but not for music. FLVs from Flash video chats (Yahoo Messenger, Chatroulette, early Justin.tv) frequently used Nellymoser. Converting Nellymoser to MP3 is technically possible but the result depends on the original recording quality.
No. The end of Adobe Flash Player in December 2020 affects the playback of interactive .swf content in browsers, but .flv video files are independent multimedia containers that don't require Flash Player to be processed. FFmpeg, VLC, and web tools like Convertir.ai can read and convert FLV without any dependency on Adobe Flash.
Convert FLV to MP3: extract audio from the Flash era of the internet
FLV (Flash Video) is the video format created by Macromedia for Flash Player, with its roots in Macromedia's acquisition of Sorenson Spark technology in 2000. Flash Player 6 (June 2002) introduced native video support with the FLV container and the Sorenson Spark video codec (a variant of H.263). The rise of FLV as the dominant web format occurred between 2005 and 2008, coinciding with three events: the founding of YouTube in February 2005 (which adopted FLV as its delivery format from the start), the release of Flash Player 8 (August 2005) with support for the higher-quality On2 VP6 video codec, and Flash Player's 98% penetration in desktop browsers reported by Adobe in 2007. The FLV container structure is technically simple: a 9-byte header identifying the file, followed by a series of audio, video, or script data tags, each with a 24-bit timestamp (limiting FLV to 4.6 hours maximum duration) and frame data. This structural simplicity made FLV the format produced by video downloaders and streaming capture programs of that era — files that today represent significant digital audiovisual heritage: the first YouTube videos, the first Justin.tv live streams (founded 2007, Twitch's predecessor), the video clips and demos from Newgrounds during the golden age of Flash (2000–2010).
The audio codec landscape within the FLV container reflects Flash's technical evolution during its decade of dominance. In early YouTube FLVs (2005–2006), audio was MP3 (MPEG-1 Audio Layer III) at 128 kbps mono or stereo — a pragmatic choice because MP3 was the only audio codec Flash Player 6 supported for streaming. Flash Player 9 Update 3 (October 2007) added AAC support (ISO/IEC 14496-3), which YouTube adopted for high-definition (720p) videos that it began supporting in March 2008. The Nellymoser codec (developed by Nellymoser Inc., a San Francisco company founded in 2000) is the third relevant codec in the FLV ecosystem: it was the de facto codec for low-latency audio in real-time Flash applications, such as the first Flash-based video chat systems (Yahoo Messenger Video, early Chatroulette), multiplayer Flash games with voice communication, and the first live audio streaming transmissions via RTMP (Real-Time Messaging Protocol, Adobe's streaming protocol). Nellymoser operates at 5, 8, 11, or 16 kbps with sample rates of 5512, 8000, 11025, or 16000 Hz, designed for minimum latency over dial-up and low-speed DSL connections.
The official shutdown of Adobe Flash Player on December 31, 2020 did not eliminate existing FLV files, but it did create urgency for their preservation. Digital archive organizations like the Internet Archive have worked systematically on Flash content preservation, including the Ruffle project (a Flash emulator in WebAssembly) for interactive .swf content. For .flv video files, conversion to modern formats (MP4, MP3) is the standard preservation strategy. In the cultural context, Newgrounds FLVs from the 2003–2010 era represent a significant part of the history of animation and independent music on the internet: artists like TomFulp (Newgrounds founder), LittleKuriboh (creator of Yu-Gi-Oh Abridged, 2006), and Egoraptor (2006–2012) published their work as FLV on Newgrounds before migrating to YouTube. Extracting audio from those FLVs preserves the original soundtracks of that era. Convertir.ai processes FLVs entirely in the browser using WebAssembly, without requiring FFmpeg installation or any Flash decoder, making audio extraction from this digital heritage accessible to any user.