Free online WMV to AVI converter

A legacy video editor, media player, or hardware device may accept AVI files but reject WMV files. Converting the file can make it usable for editing, playback, or archiving, although the result may be larger and may lose some quality.

What WMV is

WMV (Windows Media Video) is a Microsoft video format commonly stored in an ASF container and usually identified by the .wmv extension. WMV files can use codecs from the Windows Media family, including WMV1, WMV2, WMV3, and VC-1; Windows Media Audio is commonly used for sound.

WMV is found in exports from Windows Movie Maker, Windows Media Encoder, Microsoft Expression Encoder, older screen-recording programs, and legacy Windows applications. Windows Media Player can play many WMV files, but it is primarily a playback application rather than a general-purpose converter.

What AVI is

AVI (Audio Video Interleave) is a Microsoft container format that can hold video and audio encoded with different codecs. It remains supported by older editing software, industrial video equipment, archival workflows, and applications that require an .avi filename.

AVI can be a practical target because many desktop programs support common AVI combinations such as MPEG-4 Part 2 video with MP3 audio. The extension alone does not determine compatibility: an AVI containing an unusual codec may fail in the same program that accepts another AVI file.

Convert the file with FFmpeg

FFmpeg provides consistent codec and quality controls on Windows, macOS, and Linux. Open a terminal in the folder containing the source file and run:

ffmpeg -i input.wmv -c:v mpeg4 -q:v 3 -c:a libmp3lame -b:a 192k output.avi

Replace input.wmv with the actual source filename and output.avi with the destination filename. This command encodes MPEG-4 Part 2 video and MP3 audio, a combination accepted by many older applications. With FFmpeg's native MPEG-4 encoder, lower -q:v values generally produce higher quality and larger files; values from 2 to 5 are common starting points.

To reduce the output size for a device with specific limits, add scaling or frame-rate options. This example limits the width to 1280 pixels and converts the frame rate to 30 frames per second:

ffmpeg -i input.wmv -vf scale=1280:-2 -r 30 -c:v mpeg4 -q:v 4 -c:a libmp3lame -b:a 128k output.avi

Omit -vf scale=1280:-2 and -r 30 to preserve the source dimensions and frame rate. Changing either value can remove detail or alter motion, so use those options only when the target device or editor requires them.

Convert the file with desktop software

In VLC Media Player, open Media → Convert / Save, add the WMV file, select Convert, and choose a profile with AVI as the container. If the profile exposes codec settings, select MPEG-4 video and MP3 audio, specify a destination filename ending in .avi, and start the conversion. VLC offers fewer encoding controls than FFmpeg, so check the resulting file in the target application.

For conversion without installing desktop software, 101convert.com can convert WMV files to AVI for free in a browser. Upload the file, select AVI as the output format, start the conversion, and download the result when processing finishes.

Quality and compatibility limits

Most conversions require transcoding: the WMV video is decoded and encoded again for AVI. Because WMV is often lossy, re-encoding can reduce detail, introduce additional compression artifacts, and produce a file substantially larger than the source. Converting to AVI does not restore quality already lost in the WMV file.

Stream copying avoids another generation of compression and is possible only when the source video and audio codecs are valid in the AVI container and supported by the target software:

ffmpeg -i input.wmv -c copy output.avi

This command is fast and does not re-encode, but it may create an AVI that older programs cannot decode. Use the re-encoding command when broad compatibility is more important than preserving the original streams.

Metadata, subtitles, variable frame timing, and other WMV-specific features may not transfer cleanly. DRM-protected media cannot be converted unless the software has legitimate access to decode it. Test the output in the exact editor, player, or device that will use it, because AVI compatibility depends on the codecs inside the container as well as the .avi extension.