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SRT generator

Make an SRT subtitle file from any video or recording, timed to the speech. Free, with no upload or watermark.

Files stay on your device

Drop a video or recording to make its subtitles

The speech is recognized on your device, so nothing is uploaded and there's no limit on length.

MP3, M4A, WAV, FLAC, and other audio, or a video with sound.

How to make an SRT file

Open a video or recording and Mastershot listens to it on your device, then writes subtitles timed to the speech in short lines that are easy to read. Download them as an SRT file for YouTube, Premiere, DaVinci Resolve, or any player, or as VTT for the web.

  1. Step 1

    Choose a file
    Pick a video or recording, or drop it above.

  2. Step 2

    Make the subtitles
    Lines are timed to the speech on your device.

  3. Step 3

    Download the SRT
    Add it to YouTube, your editor, or your player.

What to expect

Supported inputs
Videos and recordings this browser can read: MP4, MOV, WebM, MKV, MP3, M4A, WAV, and more.
What happens
Whisper, a speech recognition model, writes down each word with its time. Words are grouped into lines of up to about 42 characters that end with a sentence, a pause, or a comma, and each line shows for as long as it's said.
Limits
The first time, the browser downloads the 77 MB speech model and keeps it. Making subtitles takes about a sixth of the recording's length. Check names and unusual words before you publish.

Private by design

Your video stays on your device

Mastershot processes your file locally in this browser. It does not need to be uploaded to a server, and you do not need an account to use the tool.

  • No upload
  • No signup
  • No watermark

Questions

A plain-text subtitle file. Each line has a number, the times it shows from and to, and its text. Almost every video site, editor, and player can read one.

Upload it next to the video on YouTube or Vimeo, or drag it onto the timeline in your editor. To burn the subtitles into the picture, use Add subtitles to video.

Yes. An SRT file is plain text, so any text editor can change a word or a time. Add subtitles to video lets you edit the lines before burning them in.

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