Convert QuickTime (.qt) to WebM Video (.webm) online for free. Fast, secure video conversion with no watermarks or registration.
Conversion settings — add a file to adjust
Upload your .mov 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 .webm file when it's ready.
WebM is Google's open, royalty-free multimedia format specifically designed for the web. It pairs VP8 or VP9 video with Vorbis or Opus audio in a Matroska-based container. VP9, the recommended video codec, achieves quality comparable to H.264 while remaining completely patent-free. Converting QuickTime files to WebM produces web-optimized video that plays natively in Chrome, Firefox, Edge, and Opera without any plugins or licenses.
QT files don't play in web browsers and require QuickTime Plugin (long deprecated) or transcoding. WebM is one of the two formats universally supported in HTML5 video (alongside MP4). For open-source web projects, WebM avoids H.264's patent licensing obligations. Google also optimizes YouTube's internal processing for VP9/WebM.
FFmpeg encodes QT video to VP9 using libvpx-vp9 with two-pass encoding for optimal quality distribution. Audio is encoded to Opus at 128 kbps (or Vorbis for older browser compatibility). The WebM/Matroska container uses a cues element at the file start for fast seeking. VP9 encoding uses CRF 31 with the 'good' quality deadline for a practical speed/quality balance.
VP9 at CRF 31 produces quality comparable to H.264 at CRF 23 — the codecs use different CRF scales. The output is visually excellent for web delivery. VP9's efficiency advantage over VP8 and H.264 is most pronounced at lower bitrates and higher resolutions.
| Device | MOV | WebM |
|---|---|---|
| Windows PC | Partial | Partial |
| macOS | Partial | Partial |
| iPhone/iPad | Partial | Partial |
| Android | Partial | Native |
| Linux | Partial | Native |
| 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
QT to WebM conversion produces web-native, patent-free video with excellent quality. It's the ideal format for open-source web publishing and provides efficient compression for Google's web ecosystem.
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
| Native |
| 特性 | MOV | WebM |
|---|---|---|
| 全称 | Apple QuickTime Movie | WebM Video |
| 扩展名 | .mov | .webm |
| 最适合 | High quality | Web optimized |