How XCaptions works

What are the steps?

1. Open a video

   Videos longer than 10 minutes are shortened to the first 10 minutes, and you can choose another part. The file is prepared locally and stays on your device.

2. Generate word-timed subtitles

   XCaptions extracts the audio in your browser, splits it into roughly 120-second chunks and sends one chunk at a time to a speech-to-text service, which returns captions with per-word timings.

3. Edit the captions

   Fix text, retime words, split or merge lines, and add or delete captions. Editing runs on your device.

4. Choose a style and ratio

   Pick one of the caption styles, adjust colours or fonts, and reframe to 9:16, 1:1, 4:5, 16:9 or the original ratio.

5. Translate if you need to

   Translate captions into English, Urdu, Roman Urdu, Hindi, Roman Hindi or Arabic, and switch between the original and the translation.

6. Trim and export

   Set the start and end, then export SRT, VTT, TXT, audio, or a captioned video at 480p, 720p, 1080p or the original size.

7. Come back later

   Projects auto-save in your browser, and the editor keeps up to three of them. Nothing is stored on the server.

What happens on my device, and what leaves it?

Everything you can see happens in your browser: opening the video, editing captions, styling, trimming, previewing and exporting the video. Only two things leave your device, and only when you ask for them. Generating subtitles sends the extracted audio to a speech-to-text service, and translating sends the caption text. Neither is stored by XCaptions. Details are on the privacy page.

What are the limits?

Videos longer than 10 minutes are automatically shortened to the first 10 minutes, and you can choose another part of the original. Files above 500 MB are locally prepared to fit the media size limit; source files above 4096 MB cannot be processed. Audio is transcribed in short chunks of about 120 seconds, and you can retry a single part. Free provider quotas for transcription and translation can also apply, and video export is the heaviest step, so keep the tab open while it finishes.