Convert Advanced Systems Format (.asf) to Matroska Video (.mkv) online for free. Fast, secure video conversion with no watermarks or registration.
Conversion settings — add a file to adjust
Upload your .asf file by dragging it into the upload area or clicking to browse.
Choose your output settings. The default settings work great for most files.
Click Convert and download your .mkv file when it's ready.
MKV (Matroska Video) is an open-source container format that can hold virtually any combination of video, audio, and subtitle codecs — including the WMV and WMA streams found inside ASF files. Converting ASF to MKV is often a remuxing operation (no re-encoding), which means the original video and audio quality is preserved perfectly while gaining MKV's superior features like multiple audio tracks, soft subtitles, and chapter support.
MKV offers capabilities that ASF lacks: unlimited audio tracks, multiple subtitle streams (SRT, ASS, PGS), chapter markers, attachments (fonts, cover art), and broad playback support on VLC, Kodi, Plex, and Android. MKV is also the standard container for high-quality archival of video content. Converting from ASF to MKV preserves quality while gaining a more feature-rich, future-proof container.
When remuxing, the WMV video and WMA audio streams are extracted from the ASF container and placed directly into the MKV (Matroska) container without re-encoding. This is nearly instant and preserves quality perfectly. The MKV header stores codec information, track IDs, and optional tags. If re-encoding is preferred, the video can be transcoded to H.264/H.265 and audio to AAC/Opus for wider direct playback compatibility.
Remuxing preserves the exact original quality — it is a container change only, not a codec change. If you choose to re-encode, quality depends on the target codec and bitrate settings. For archival, remuxing is strongly recommended to avoid any generational loss.
| Device | ASF | MKV |
|---|---|---|
| Windows PC | Partial | Partial |
| macOS | Partial | Partial |
| iPhone/iPad | Partial | Partial |
| Android | Partial | Partial |
| Linux | Partial | Partial |
| Web Browser | No |
Resolution: 1920x1080
Bitrate: 8-12 Mbps
H.264 recommended for fast processing
Resolution: 1080x1080
Bitrate: 3.5 Mbps
Square or 9:16 for Reels
Resolution: 1080x1920
Bitrate: 4 Mbps
9:16 vertical, under 60s ideal
Resolution: 1280x720
Bitrate: 5 Mbps
Under 140s, 512MB max
Resolution: 960x540
Bitrate: 2 Mbps
16MB limit for standard, 64MB for document
Resolution: 1280x720
Bitrate: 4 Mbps
8MB free, 50MB Nitro
ASF to MKV conversion gives you a modern, open-source container with superior features while optionally preserving the original quality through remuxing — the best archival choice for Windows Media content.
安全传输
HTTPS 加密上传
隐私优先
文件处理后自动删除
无需注册
即刻开始转换
随处可用
任何浏览器，任何设备
| No |
| 特性 | ASF | MKV |
|---|---|---|
| 全称 | Advanced Systems Format | Matroska Video |
| 扩展名 | .asf | .mkv |
| 最适合 | Streaming optimized | Multiple audio tracks |