Convert WMV to OPUS Online
Convert corporate WMV meeting recordings to modern Opus audio, free and in your browser.
.wmv · up to 100 MB
Why use this tool
Modernize your corporate WMV archive
Files up to 50% smaller
Opus compresses voice audio better than WMA. Ideal for archiving meetings without wasting storage.
Discord and VoIP ready
The resulting .opus file works natively in Discord, Mumble, WebRTC, and all modern communication platforms.
No server, no signup
FFmpeg.wasm processes your file locally in the browser. Your corporate recordings never leave your device.
Modernize Lync and Skype archives
Convert your legacy WMV recordings from Lync 2010/2013 and Skype for Business to a format with active long-term support.
How it works
Three steps, no hassle
Upload your WMV file
Drag or select your .wmv file. Works with meeting recordings, Lync archives, and Skype/Teams exports in WMV format.
FFmpeg converts audio locally
The WMA audio track inside the WMV is decoded and re-encoded to Opus 48 kHz using FFmpeg.wasm — nothing is uploaded to any server.
Download your .opus file
Get an Opus file compatible with Discord, VoIP platforms, and modern media players. Up to 50% smaller than MP3 at equivalent quality.
FAQ
Got questions?
WMV uses Microsoft's proprietary ASF container with WMA (Windows Media Audio) audio, introduced in 1999. Lync 2010/2013 and Skype for Business generated WMV recordings with WMA audio at 128 kbps or WMA Pro at 192 kbps. Opus achieves the same perceptual quality at 64–96 kbps, reducing audio file size by up to 50% with no audible difference.
The conversion extracts only the audio track from the WMV and re-encodes it to Opus. The video is discarded. If you need to keep the video, consider converting to MP4 first. For voice archives or audio-only uploads, Opus is the ideal output format.
Yes. Discord has used Opus internally for all voice transmission since 2015, with the Opus VOIP profile at 64 kbps. OGG-encapsulated .opus files are accepted as Discord chat attachments and play inline. Mumble, TeamSpeak 3 (since 2014), and all WebRTC-based platforms use Opus as their native codec.
Yes. Local recordings from Skype for Business (formerly Lync) and legacy Teams exports in WMV format are fully supported. This is a common path for modernizing Lync Recording Manager archives or on-premise Teams recordings stored as WMV on corporate servers.
Depends on file size and device performance. A 1-hour corporate meeting WMV (typically 200–400 MB) takes between 30 seconds and 2 minutes on a modern computer. FFmpeg.wasm uses WebAssembly and can leverage multi-threaded execution when the browser supports it.
There is one transcoding generation: WMA is decoded to PCM, then re-encoded to Opus. However, Opus is technically superior to WMA in compression efficiency. At 64 kbps, Opus outperforms WMA at 128 kbps in MUSHRA perceptual listening tests. For corporate voice recordings, the difference is practically inaudible.
Convert WMV to Opus: modernize Lync, Skype for Business, and Teams meeting recordings
WMV (Windows Media Video) was introduced by Microsoft in 2003 as part of the ASF (Advanced Systems Format) standard, a proprietary container designed for progressive streaming in Windows Media Player. Audio in WMV files uses WMA (Windows Media Audio), a proprietary Microsoft codec introduced in 1999 as a competitor to MP3, later extended to WMA Pro (multichannel, 2003) and WMA Lossless (2004). Through the first decade of the 2000s, WMV became the default corporate format for meeting recordings in Microsoft environments. Lync Server 2010, released December 1, 2010, used the Lync Recording Manager to save recordings in WMV format. Its successor, Skype for Business (released April 14, 2015 alongside Office 365), maintained the same behavior for local recordings until Microsoft Teams began replacing it from 2018 onward. The result is that many organizations accumulated large libraries of corporate meeting recordings in WMV format during 2010–2020, with WMA audio that is now incompatible with modern communication platforms, cloud storage systems, and collaboration tools.
Opus was standardized by the IETF as RFC 6716 in September 2012 and represents the state of the art in lossy audio compression for voice and music applications. Unlike WMA, which is a proprietary Microsoft format with no guaranteed long-term support, Opus is an open, royalty-free standard actively maintained by the IETF and universally adopted in WebRTC, Discord (since 2015), Zoom, Google Meet, and virtually every real-time communication platform launched after 2013. For corporate voice audio, the efficiency difference is significant: Opus at 64 kbps outperforms WMA at 128 kbps in perceptual quality, translating to files up to 50% smaller at equivalent quality. For a library of 500 hours of Lync meeting recordings, this can mean the difference between 200 GB and 100 GB of storage. Additionally, Opus at 32 kbps is perfectly intelligible for voice audio, enabling even more aggressive compression for long-term archival.
Convertir.ai runs the WMV→Opus conversion entirely in the browser using FFmpeg.wasm, the WebAssembly build of FFmpeg published by the ffmpeg.wasm project in 2019. The technical process: FFmpeg opens the ASF container of the WMV, detects the WMA audio track (codec_name wmav2 or wmalossless depending on the recording settings), decodes it to float32 PCM at the original sample rate (typically 44.1 kHz or 48 kHz in corporate recordings), resamples to 48 kHz if needed (Opus operates exclusively at 48 kHz internally), and re-encodes with libopus at 64 kbps in VOIP mode (optimized for voice signals) by default. The result is a .opus file in OGG container conforming to RFC 7845, directly playable in Discord, VLC 2.1+, mpv, Firefox 15+, Chrome 25+, and any WebRTC client. Metadata available in the ASF segment (title, date, participant names if recorded by Lync Recording Manager) is transferred to the OpusTags of the resulting file. The service is completely free, no usage limits, no signup, and no watermark.