WebM to MP4 Converter
Convert WebM to MP4 online for free: nothing to install, no watermark, files encrypted in transit and deleted automatically after conversion.
Advanced options
Drag & drop your WEBM file here, or
How to convert WebM to MP4 in 3 steps
- 1
Upload your WebM file
Drag and drop or select the WebM file you want to convert.
- 2
Choose MP4 as output
The output format is pre-selected for you — just confirm and start the conversion.
- 3
Download your file
Once processing finishes, download your converted MP4 file instantly.
Converting WebM to MP4: what to know
When you need it
WebM videos come from screen recorders, browser extensions and websites. iPhones, video editors, presentation software and some social networks prefer MP4, so converting avoids “unsupported format” errors.
What to expect
WebM usually holds VP8 or VP9 video, which MP4 players don't expect, so the video is re-encoded to H.264 with AAC audio. That takes longer than a simple copy, and the MP4 may be somewhat larger than the WebM.
Tip: Convert to MP4 when you need to edit or share the video; if it is only for your own website, the WebM is already the lighter option.
WebM vs MP4: what is the difference?
| WebM | MP4 | |
|---|---|---|
| Full name | WebM | MPEG-4 Part 14 |
| Type | Video container | Video container |
| Compression | Lossy | Depends on the codec |
| Developed by | MPEG (ISO/IEC) | |
| File extension | .webm | .mp4 |
What is WebM?
WebM is an open, royalty-free video format backed by Google and designed for the web. It uses VP8, VP9 or AV1 video with Opus or Vorbis audio, plays natively in modern browsers and keeps files small, though some editors and Apple devices handle it poorly.
What is MP4?
MP4 is the most widely used video container. It usually carries H.264 or H.265 video with AAC audio, and it plays on practically every phone, browser, smart TV and editing program, which makes it the safest choice for sharing and uploading.
Tips for converting WebM to MP4
- Check the length and resolution of your WebM file first: long 4K videos take several minutes to process and may exceed the 50MB free limit.
- If you only need the soundtrack, pick an audio format such as MP3 instead of MP4 — the file will be much smaller.
- Keep the original video until you have checked the converted file plays correctly on the device you want to use.
- Subtitles and extra audio tracks are not always carried over between containers, so check them after converting.
Frequently asked questions
- How do I convert WebM to MP4 online?
- Upload your WebM file above, select MP4 as the output format, and click Convert. ConvertFastHub processes the file in the cloud and gives you a download link — no software installation required.
- Is it free to convert WebM to MP4?
- Yes. Free accounts get 10 conversions every 24 hours with files up to 50MB. For unlimited conversions, larger files up to 1.5GB, and priority processing, upgrade to ConvertFastHub Pro.
- Is my file safe when I convert it?
- Files travel over an encrypted connection, are scanned automatically for malware (files up to 200 MB), are processed in an isolated worker and are deleted automatically: after 1 hour without an account, 24 hours with a free account, or 7 days with Pro.
- Can I convert WebM to MP4 on my phone?
- Yes. The converter runs in the browser and the work happens on our servers, so it works the same on Android, iPhone, tablets and computers — there is no app to install.
- Do I need an account?
- No. You can convert without signing up; results are then kept for 1 hour. A free account keeps them for 24 hours and shows your conversion history.