WMV vs MP4 — Comparison & Free Converter
Fast, instant WMV to MP4 conversion. No signup required. Just drop your .wmv file and get .mp4 in seconds.
Batch Settings
Generation loss — quality may degrade
WMV uses lossy compression, and so does MP4. Converting means decoding and re-encoding — each cycle can permanently degrade quality. Convert from the original source file whenever possible.
Some metadata may not survive
Your WMV file may contain ASF metadata, DRM tags metadata. MP4 has limited or no support for these metadata types. Location data (GPS), camera settings, and color profiles may be stripped during conversion.
What compression artifacts to expect
MP4 lossy compression can produce blockiness, banding in gradients, mosquito noise. At the high quality settings CocoConvert uses by default, these are usually invisible to the eye. Lower quality settings trade visual fidelity for smaller file sizes.
長年親しまれてきたWMV形式ですが、今日の多様なデバイス環境やWeb配信の場面では、より汎用性の高いMP4形式への変換が不可欠となることが増えてまいりました。特に、日本国内のビジネスシーンやクリエイティブな分野では、資料の共有、プロモーションビデオの展開、あるいは個人的な思い出のアーカイブに至るまで、動画の互換性は作業効率を大きく左右します。本ツールは、大切なWMVファイルを品質を損なうことなく、スムーズにMP4へと変換できるよう設計されています。複雑な設定は不要で、直感的な操作性でどなたでも簡単にご利用いただけます。お使いのフォントや縦書き表示を考慮したコンテンツでも、変換後のMP4が様々な環境で正しく表示されるよう、細心の注意を払っておりますのでご安心ください。
- アニメ・漫画同人イベントでの映像作品共有
- ビジネス会議資料の動画ファイル互換性向上
- ガラケー時代の動画をスマホで再生
日本では、Windows Media PlayerがプリインストールされていたPCが多かったためWMVファイルが広く普及しましたが、Macユーザーやスマートフォンの普及に伴い、互換性の問題が顕在化しました。
About WMV to MP4 Conversion
WMV or MP4 — which format should you use? The answer depends on your needs. Here's a quick breakdown.
WMV (Windows Media Video) is Microsoft's proprietary format, common in older Windows ecosystems. It has limited platform support. MP4 (MPEG-4 Part 14) is the universal video container supporting H.264/H.265 codecs — plays on virtually every device. It has universal platform support.
Full Name: WMV uses Windows Media Video, while MP4 uses MPEG-4 Part 14. Compression: WMV uses Lossy, while MP4 uses Lossy. Color Depth: WMV uses 8-bit, while MP4 uses 8-bit (H.264) or 10-bit (H.265/AV1).
So when should you convert WMV to MP4? This conversion is ideal when you Your WMV file won't open on a recipient's device or in an application, or when you A website, service, or platform only accepts MP4 uploads. This conversion helps you improve file compatibility across devices.
WMV uses lossy compression, and so does MP4. Converting means decoding and re-encoding — each cycle can permanently degrade quality. Convert from the original source file whenever possible. Common misconception: ""I'll convert to MP4 and then back to WMV — it'll be the same"" — in reality, each lossy conversion cycle permanently degrades quality. going wmv → mp4 → wmv will produce a noticeably worse file than the original. always keep your source file.
If you've decided MP4 is the right choice, CocoConvert makes the conversion effortless. Upload your .wmv file, pick MP4, and click Convert — done in seconds. The converter runs on secure servers in Germany, powered by FFmpeg, Sharp, and qpdf. Files are encrypted via TLS and erased within 24 hours.
Free tier: 5 files/hour, 250 MB each. Pro: 100 files/hour, 5 GB each. Works in every modern browser on desktop and mobile.
How to Convert WMV to MP4
- 1
Choose your WMV file
Upload your .wmv file using drag-and-drop or the file browser. Batch mode lets you add multiple files.
- 2
Set format to MP4
Select .mp4 from the output options. The converter applies optimal quality settings automatically.
- 3
Run the conversion
Click Convert. Server-side processing means your device stays fast — even for large video files.
- 4
Get your MP4 file
Download your converted file instantly. Batch downloads are available as a zip archive.
What Happens When You Convert WMV to MP4
Your WMV video is transcoded — video and audio streams are decoded and re-encoded into the MP4 container. This is a lossy process that takes time proportional to the video duration.
Your WMV file is demuxed — video, audio, and subtitle streams are separated
The video stream is decoded frame-by-frame, then re-encoded with MP4-compatible codecs (typically H.264 for MP4)
The audio stream is decoded and re-encoded (or copied if the codec is compatible)
Subtitle and chapter data is preserved where the target supports it
Streams are muxed into the MP4 container and the file is saved
WMV vs MP4 — Detailed Comparison
| Feature | .WMV | .MP4 |
|---|---|---|
| Full Name | Windows Media Video | MPEG-4 Part 14 |
| Compression | Lossy | Lossy |
| Color Depth | 8-bit | 8-bit (H.264) or 10-bit (H.265/AV1) |
| HDR Support | No | Yes |
| Typical File Size | 30–100 MB per minute | 50–200 MB per minute (1080p H.264) |
| Platform Support | Limited | Universal |
| Browser Support | none | Universal |
| Year Created | 1999 | 2001 |
| Open Standard | No | Yes |
Should You Convert WMV to MP4?
When to Convert
- ✓Your WMV file won't open on a recipient's device or in an application
- ✓A website, service, or platform only accepts MP4 uploads
- ✓You need a file that works in web browsers
- ✓You need maximum device and software compatibility
When NOT to Convert
- ✗You're converting just because the file "seems old" — re-encoding lossy-to-lossy always degrades quality
Common Mistakes When Converting WMV to MP4
"I'll convert to MP4 and then back to WMV — it'll be the same"
Each lossy conversion cycle permanently degrades quality. Going WMV → MP4 → WMV will produce a noticeably worse file than the original. Always keep your source file.
Frequently Asked Questions
Should I use WMV or MP4?
It depends on your goal. WMV offers smaller files via lossy compression. MP4 offers smaller files via lossy compression. Choose based on whether file size or quality matters more for your use case.
Is MP4 higher quality than WMV?
Not necessarily. WMV uses lossy compression, and so does MP4. Converting means decoding and re-encoding — each cycle can permanently degrade quality. Convert from the original source file whenever possible. Quality depends on the compression type and settings, not just the format name.
Can I convert WMV to MP4 on Mac and Windows?
Yes. CocoConvert is a web-based tool that works in all modern browsers — Chrome, Safari, Firefox, Edge — on any operating system including macOS, Windows, Linux, iOS, and Android.
Is CocoConvert free for WMV to MP4?
Yes. Free users get 5 conversions per hour (250 MB each). Pro subscribers unlock 100 files per hour, 5 GB per file, and priority processing.
What tools does CocoConvert use for WMV to MP4?
CocoConvert uses FFmpeg for audio/video, Sharp for images, and qpdf for documents — the same open-source libraries used by Netflix, YouTube, and major enterprise platforms.
Versions are pinned in our worker Dockerfile and re-built via CI on every change.