Subtitle Generator — Auto Captions
Generate SRT and VTT subtitles from any video or audio with speech recognition that runs on your device.
How to convert Video to Subtitles
- 1
Choose your Video file
Click the upload area or drag files onto it. Nothing is uploaded — files are opened locally.
- 2
Start the conversion
Press the convert button. Your browser converts the files in seconds.
- 3
Download the result
Save each file individually or everything at once as a ZIP.
Add captions to a lecture, interview, reel or meeting recording without uploading it anywhere. Speech is transcribed with timestamps by an AI model that runs in your browser, and you get both SRT (for YouTube and editors) and VTT (for web players). English speech; the first run downloads the speech model (about 40 MB).
Read the full guide with screenshotsWhat is Video?
MP4, MOV and WebM videos are supported as input.
What is Subtitles?
SRT and WebVTT are the standard subtitle formats for YouTube, video players and editors — timed lines of text.
Is it private?
Yes. Unlike upload-based converters, ZapMorph processes files inside your browser tab, so the file stays on your device. It is never transmitted, stored or logged — close the tab and it’s gone.
Frequently asked questions
Is the subtitle generator — auto captions converter free?
This is a Pro tool. With a free account you get one run a day to try it; Pro and Lifetime plans include unlimited use.
Are my files uploaded to a server?
No. The conversion runs entirely in your browser, so your files never leave your device. We only count how many files you convert — never their names or contents.
What is the maximum file size?
Up to 25 MB per file without an account, 50 MB with a free account, and 1 GB on Pro. Very large files also depend on your device’s memory.
Can I convert multiple Video files at once?
Subtitle Generator — Auto Captions works on one file at a time and can produce many output files, which you can download together as a ZIP.
Does it work on Mac, Windows, iPhone and Android?
Yes. It works in any modern browser — Chrome, Edge, Firefox and Safari — on desktop and mobile, with nothing to install.
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