Step 1
Upload video
Upload your MP4 video file to Sonix and select the language.
Add subtitles to MP4 videos
Sonix automatically transcribes your MP4 video and lets you add professional subtitles with customizable styling.
Auto-transcribe
Custom styling
Burn-in option
Audio
Video
DOCX
SRT/VTT
PDF
53+ Languages
10x
Faster than real-time
Add subtitles to MP4 in minutes
99%
Accuracy rate
Industry-leading AI transcription
53+
Languages
Subtitles in any language
Custom
Styling
Fonts, colors, positioning
Add subtitles to MP4 in 4 steps
Step 2
Auto-transcribe
Sonix AI transcribes your video with word-level timestamps.
Step 3
Customize subtitles
Split subtitles, adjust timing, and customize fonts and colors.
Step 4
Export or burn-in
Download SRT/VTT files or burn subtitles directly into your video.
Everything about adding MP4 subtitles
Can Sonix add subtitles to MP4 videos?
Yes! Upload your MP4 video, and Sonix will transcribe it and let you add professional subtitles with customizable styling.
Can I burn subtitles into the video?
Yes! Sonix can permanently embed (burn-in) subtitles into your MP4 video with your choice of fonts, colors, and positioning.
What subtitle styles are available?
Customize fonts, colors, background boxes, positioning (top, center, bottom), and more for your burned-in subtitles.
Can I download subtitle files separately?
Yes! Export subtitles as SRT, VTT, or other formats to use with YouTube, Vimeo, or your video editor.
Can I translate subtitles to other languages?
Absolutely! Sonix can translate your subtitles into 54+ languages for multilingual videos.
How do I split subtitles correctly?
Sonix offers auto-split options for max characters per line, lines per caption, and max duration. Fine-tune manually if needed.
The easiest way to add video subtitles
Auto-Transcribe
Upload your MP4 and get accurate subtitles automatically.
Custom Styling
Choose fonts, colors, and positioning for professional results.
Burn-in Option
Permanently embed subtitles into your video with one click.
Translate
Create subtitles in 53+ languages from your original video.
More ways to work with MP4 files
Other MP4 conversions
Trusted by video creators
Unbelievable! Wow, it's amazing. Really amazing. I didn't believe it so I wanna test something and I got actually result I wanted. Amazing!
Sooooooooooo easy to use and accurate.
It's incredibly fast, and it sets the timing for subtitles perfectly. I dread having to time everything myself, and with Sonix I can do that just by pressing Enter!
English dictation is very accurate. And the online editor is easy to use. Also it generates SRT files that I can import in my video editors for further processing.
I am a video editor and I found you by trying a few services with free trials. Sonix was far, far superior as well as an easy process to trial enroll.
I tried Sonix, and it’s amazing! Seriously, I think that you will revolutionize journalism.
Wow. SPEED. Nice format, easy to read, liked the time stamps and speaker notification. Not a lot of formatting I had to strip before using. Simple.
The interface and editor experience were great. I also like the way you handle speaker identification and naming. Pretty slick. Nice timestamp frequency / formatting too.
Add subtitles to MP4 now
Try Sonix free with 30 minutes of transcription. No credit card required.
