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
I love Sonix. It's accurate, intuitive, friendly and simple to use for the technically inept like me! I typically use it for English but we used it this time in French and it was great too.
What I loved about the transcription is that it is fast and it's also highly accurate.
I found out out you guys because I had to do some transcribing for me yearbook class and my friend recommended you guys. It was a very easy process and it took hours off the time I had to a...
Sonix saves me 60% of the time editing. No more manual trascription nightmare with writing down timecodes, and sending emails. I think you are changing the game here! Bravo :)
Transcription was almost perfect!!
Of all the programs that do this, I found you the best!
In one word? FAN-TAS-TIC!! The possibility to split the transcript to subtitles AND split them! THAT IS FANTASTIC!!
The highest accuracy I have ever achieved through similar services.
Add subtitles to %{v_extension} now
Try Sonix free with 30 minutes minutes of transcription. No credit card required.
