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
The process was super easy. I liked that you can upload video file without stripping away the audio first to do it, this of course saves production time. Great job overall for sure!!!
Found you through Google. Super easy to use. Transcribed 98% correctly even though it was not a great audio file.
I've tried several different digital software packages and nothing has even approached giving me a usable transcription. The results from Sonix are the best I've seen. And fast. I'...
The transcript came through almost word perfect from a video file. Your system is absolute MAGIC!
Sonix's transcription and translation features are stunningly accurate, I'm very impressed.
I am LOVING Sonix! The price, accuracy, create your own library, check marks when something is completed. I am so glad I found the service.
Sooooooooooo easy to use and accurate.
I have absolute admiration for the impressive transcription done to 3 short YouTube videos. It is truly amazing how accurately it recorded the correct words and so well paragraphed...
Add subtitles to MP4 now
Try Sonix free with 30 minutes of transcription. No credit card required.
