21 — Subtitle

Keep text concise and on-screen long enough for a person to read comfortably.

Widely reviewed as the "best free subtitling tool," it has recently added features like AI audio-to-text (using Whisper or Vosk) and the ability to burn-in subtitles directly into the video. subtitle 21

Include non-speech elements like [glass breaks] or [mysterious music] to ensure accessibility for the deaf and hard of hearing. Keep text concise and on-screen long enough for

Its Studio version now includes an AI audio transcriber that generates animated, stylish captions automatically. Subtitling Best Practices subtitle 21

This is the newer digital standard. Unlike Line 21, it allows viewers to change the appearance of captions, such as text size and background transparency.

Subtitles must align perfectly with the audio to avoid confusing the viewer.