How to convert MOV to WebM
- Click Choose files or drop your MOV video into the box above.
- Keep the default quality, or choose a target size, resolution or frame rate.
- Click Convert and download the WebM when it is ready.
MOV vs WebM
| MOV | WebM | |
|---|---|---|
| Usual codecs | H.264 or H.265 (HEVC) from iPhones, ProRes from cameras, with AAC audio | VP8, VP9 or AV1 video with Opus or Vorbis audio |
| Plays on | Apple devices natively; on Windows, Android and many websites support is hit-and-miss (especially for HEVC) | Chrome, Firefox, Edge and Android; partial support on iPhone and Mac; not accepted by many editors |
| Best for | Recording and editing on iPhone and Mac | Video embedded in websites and screen recordings |
| Introduced | 1991 by Apple | 2010 by Google |
About MOV and WebM
What is MOV?
MOV is Apple’s QuickTime format and what an iPhone records by default. MP4 was actually derived from it, so most MOV files contain the same kind of video and can often be converted to MP4 in seconds without re-encoding. Since iOS 11, iPhones record HEVC (H.265) video, which many Windows PCs, Android phones and websites cannot play — converting to MP4 with H.264 fixes that.
- Native on iPhone and Mac
- Supports pro codecs like ProRes
- HEVC MOV files often will not play on Windows or Android
- Some websites reject MOV uploads
What is WebM?
WebM is an open, royalty-free video format designed for the web. Screen recorders and browsers often save clips as WebM. It is efficient, but many video editors, iPhones, smart TVs and upload forms do not handle it well, so WebM files are frequently converted to MP4.
- Royalty-free and efficient
- Plays in Chrome, Firefox and Edge
- Weak support in editors, TVs and some Apple apps
Why GlideConvert?
- Private by design. Your files are converted on your own device by your browser — they are never uploaded to a server. That keeps them private, avoids upload waits and means there is no queue.
- Fast. Images convert in a fraction of a second; video uses your device’s hardware encoder and is often simply repackaged without re-encoding.
- Free. No sign-up, no watermark. 10 images, 5 audio files or one video at a time — Pro lifts the limits and removes ads.
Frequently asked questions
Will converting MOV to WebM lose quality?
Often not at all. If the MOV file already contains video and audio that WebM supports (H.264 video and AAC audio are the most common), they are copied as-is: no quality loss, and even a large file converts in seconds. Otherwise the video is re-encoded at high quality — choose a quality level or a target file size in the options.
How long does converting MOV to WebM take?
Usually much less than the length of the video: modern browsers encode video with your device’s hardware. Older formats such as WMV, FLV and AVI use a slower universal decoder.
Why do my iPhone videos not play on Windows or Android?
Since iOS 11, iPhones record video with HEVC (H.265) compression to save space. Many Windows PCs, Android phones, TVs and websites cannot play HEVC. Converting to MP4 with H.264 — the default here — makes the video play everywhere.
Which codecs does the WebM use?
VP9 video with Opus audio when your browser can encode them (falling back to VP8), the standard WebM combination supported by Chrome, Firefox, Edge and Android.
Is there a file size limit?
On the free plan each video or audio file can be up to 500 MB and each image up to 100 MB. With Pro the limit is 4 GB per file. Because everything happens on your device, the practical limit for very large files is your device’s memory.
Are my files uploaded to a server?
No. GlideConvert runs entirely in your browser: images are processed with the browser’s built-in codecs and WebAssembly, video and audio with hardware-accelerated WebCodecs (or a WebAssembly build of FFmpeg for older formats). Nothing is sent anywhere — you can even disconnect from the internet once the page has loaded.
Does it work on iPhone, Android, Mac and Windows?
Yes. It works in any up-to-date browser — Chrome, Edge, Safari, Firefox or Samsung Internet — on phones, tablets and computers, with nothing to install. Long or 4K videos convert faster on a computer than on a phone.