Convert WMV to MP4
Convert Windows WMV video files to universal MP4 format. Free, in your browser, no file upload.
.wmv · up to 100 MB
Why convert WMV to MP4
From Windows to universal, without the hassle
Total privacy
Your video is processed with FFmpeg.wasm in your browser. No file ever reaches any server.
Quality preserved
We re-encode with H.264 at high quality. The visual difference from the original WMV is minimal.
Universal compatibility
MP4 with H.264 and AAC works on any device, platform, and social network without exception.
Ready instantly after first load
FFmpeg.wasm downloads once and is cached. Subsequent conversions start immediately.
How it works
Three steps, no hassle
Upload your WMV file
Drag or select your .wmv file. No registration or artificial size limit.
Automatic conversion to MP4
FFmpeg.wasm re-encodes the video to H.264 with AAC audio directly in your browser. No servers.
Download the MP4
Download the resulting MP4 file, compatible with any device, platform, and social network.
FAQ
Got questions?
WMV (Windows Media Video) is a proprietary video format developed by Microsoft in 2003 as part of the ASF (Advanced Systems Format) standard. It was designed primarily for Windows Media Player and was widely used on Windows PCs for screen recordings, old camera videos, and multimedia content distributed on CD/DVD.
WMV has no native support on macOS, iOS, Android, or Linux. It also does not play in most modern web players or social networks. MP4 with H.264 is the universal format: it works on all operating systems, mobile devices, browsers, and video platforms.
The conversion requires re-encoding to H.264, which involves some compression quality loss. However, with appropriate quality settings the difference is practically imperceptible to the naked eye. The visual quality of the resulting MP4 is comparable to the original WMV.
In general, WMV and MP4 with H.264 produce files of similar size at equal visual quality. In some cases the MP4 may be slightly smaller because H.264 is a more modern and efficient codec than the original WMV codecs (VC-1 or WMV3).
The most common sources are: old screen recordings made with Xbox Game Bar or legacy Windows recorders, digital camera videos from the 2000s–2010s, corporate archive files from companies that used Windows Media for internal distribution, and content downloaded from old video platforms.
MP4 with H.264 is compatible with absolutely all modern players: VLC, QuickTime, Windows Media Player, iPhone, Android, iPad, smart TV, YouTube, Vimeo, TikTok, Instagram, WhatsApp, and any web browser.
WMV history (Microsoft 2003), Windows Media codec, ASF container, legacy format migration
WMV (Windows Media Video) is a family of video codecs developed by Microsoft from 2003, based on the SMPTE VC-1 compression standard. The WMV format is distributed in the ASF (Advanced Systems Format) container, also proprietary to Microsoft. During the 2000s it was widely adopted in the Windows ecosystem thanks to its integration with Windows Media Player, Windows Movie Maker, and the Office suite. Digital cameras of the era and Microsoft's screen recording software generated WMV files by default.
The main problem with WMV in today's landscape is its proprietary nature and lack of cross-platform support. Apple never included native WMV support in macOS or iOS, forcing users to install Flip4Mac or other third-party plugins. Web browsers never implemented native WMV decoding. Modern video platforms (YouTube, Vimeo, TikTok) do not accept WMV as an upload format or reject it outright. This makes conversion to MP4 a necessary step for any WMV file you want to share or publish.
The technical conversion from WMV to MP4 involves transcoding: decoding the VC-1 or WMV3 stream and re-encoding it as H.264 (AVC) inside the MP4 container. FFmpeg performs this with the command ffmpeg -i input.wmv -c:v libx264 -c:a aac output.mp4. H.264 offers superior compression efficiency to VC-1 at equal visual quality, which explains why the resulting MP4 files are frequently equal to or smaller than the original WMV files. WMV audio (typically WMA) is converted to AAC, the standard audio codec in the MP4 container.