Auto-caption English videos

Automatically add accurate captions to your English videos in less than 5 minutes. Sonix extracts speech, generates perfectly-timed captions, and exports to SRT or VTT format.

5-minute processing
SRT & VTT export
YouTube compatible
Video
Captions
Timing
SRT
VTT
YouTube
5min
Caption generation
1-hour English video captioned in ~5 minutes
99%
Caption accuracy
Industry-leading English speech recognition
40+
Video formats supported
MP4, MOV, AVI, MKV, WebM, and more
SRT/VTT
Caption export formats
YouTube, Vimeo, Facebook compatible
How It Works

Auto-caption English videos
in 6 easy steps

1

Sign in to Sonix

Log in to your Sonix account or create a free trial account. Your trial includes 30 minutes minutes of free auto-captioning for English videos.

2

Upload your video

Click 'Upload' and choose the English video file from your computer that you want auto-captioned. Sonix supports 40+ video formats including MP4, MOV, and AVI.

3

Select language

Make sure you select English as the language spoken before clicking the 'Transcribe' button. Our AI will extract and transcribe all speech from your video.

4

Split into captions

Once transcribed, go to the Subtitles menu and select 'Split subtitles.' Sonix automatically splits your transcript into properly-timed caption segments.

5

Polish your captions

Review and correct any proper nouns or technical terms. Use our editor to fine-tune timing and make your English captions perfect.

6

Export captions

Click 'Export' and choose SRT or VTT format for your English captions. Ready for YouTube, Vimeo, Facebook, or any video platform.

Common Questions

Frequently asked questions about
English auto-captioning

How long does it take to auto-caption English videos?

Sonix uses cutting-edge transcription algorithms to caption your English videos in minutes. Our servers can auto-caption a one-hour English video in under 5 minutes. You can then edit and fine-tune using our powerful subtitle editor.

What caption file formats does Sonix export?

Sonix exports English captions in two industry-standard formats: SubRip (.srt) and WebVTT (.vtt). Both formats are compatible with YouTube, Vimeo, Facebook, and virtually all video platforms and players.

Can I burn captions directly into my English video?

Yes! From the Subtitles menu, you can choose to burn-in the English captions directly into your video. This creates a new video file with permanent, embedded captions that display on any device.

How accurate are English auto-captions?

Sonix delivers 85-99% accuracy for English auto-captioning, depending on audio quality. Clear audio with minimal background noise achieves the best results. Our AI models are trained specifically for English speech patterns.

Can I customize caption styling?

Yes. Sonix lets you customize font size, font color, background color, and caption positioning. These styling options are preserved when you burn captions into your video.

Do auto-captions work with YouTube?

Absolutely. Export your English captions as an SRT or VTT file and upload directly to YouTube. Your captions will sync perfectly with your video's audio.

Why Sonix

The best choice for
English video captions

Blazing fast

Get your English video captioned in minutes, not hours. Our AI processes at 10x real-time speed.

Export options

Export to SRT, VTT, or burn captions directly into your video. Compatible with all major platforms.

Easy editing

Fine-tune timing and text with our intuitive subtitle editor. Click any caption to jump to that moment.

Any video format

Upload MP4, MOV, AVI, MKV, WebM, and 40+ other video formats. No conversion needed.

Customer Reviews

Trusted by professionals worldwide

4.98 rating from 211 reviews

The level of accuracy and your UI is quite amazing. It allowed me to try the product without having to learn anything new, I was so happy about it I sent the results to a couple of...
GG
Ghislaine G.
Madrid, Spain
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.
MC
Michael C.
Aberdeen, Hong Kong
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!
AG
Ahmed G.
Dhaka, Bangledesh
I'm very happy with the experience. The Spanish translations are superb. I'm in awe!
LV
Luis V.
San Jose, Costa Rica
I love how easy it is – it saves me so much time transcribing – I can just pull out the main points of interest from the transcription.
NJ
Noreena J.
Windsor, Canada
Impressed at how seamless Sonix makes editing transcripts. This is so much easier and more enjoyable than manually writing an entire transcript myself.
SA
Sean A.
Wellington, New Zealand
Get Started

Your English video captions are
just 5 minutes away

Upload your English video and get perfectly-timed captions in minutes. Start with 30 minutes minutes free—no credit card required.

99% accuracy. Every word matters.

AI transcription and translation in 53+ languages.

30 minutes free
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