Why caption MP4 in the browser?
Captioning locally keeps private footage on your device and creates a file that does not depend on separate subtitle uploads.
Add caption to MP4
Caption an MP4 without uploading.
Drop your video here
or
MP4, MOV or WEBM · up to 500 MB on desktop, 150 MB on mobile
- 1Upload
- 2Remove audio
- 3Download
Your video stays on your device.
Add caption to MP4 use cases
When to add a caption before sharing
Add a caption when the viewer may watch without sound or when a short explanation needs to stay attached to the MP4.
Browser processing vs upload-based tools
A full caption editor is better for timed subtitles. MuteVideo is for the quick case: one clear caption, exported privately.
How it works
- 1
Choose MP4
Select the MP4 you want to caption. The source stays on your device.
- 2
Write caption
Use the Caption preset for readable text on a translucent background.
- 3
Download
Export a new MP4 with the caption baked into the video.
FAQ
Can I add subtitles to an MP4 file?
The MVP supports a single burned-in caption line. It is not a timed subtitle editor yet.
Will the caption show on every platform?
Yes. Because the caption is burned into the video image, it appears anywhere the MP4 plays.
Is my video uploaded anywhere?
No. The file is processed locally in your browser using WebAssembly. Nothing leaves your device.
Which file formats are supported?
MP4, MOV, and WEBM up to 500 MB on desktop and 150 MB on mobile.
Is there a watermark?
No. The exported video is identical to your file with the requested change applied.