Many people scroll with the sound off, and some viewers cannot hear it at all. Captions keep the trailer clear for both.
Why add them
A trailer that depends on narration alone loses the viewer who watches muted. Captions carry the hook to them.
They also make the trailer accessible to deaf and hard-of-hearing viewers.
How to do it well
Keep lines short, put them where they do not cover the main image, and keep a type size that reads on a phone.
Match the timing to the speech or the beat, so the line is readable before it disappears.
Captions or on-screen lines
Captions transcribe what is said. On-screen lines are part of the design and carry the story on their own. A good trailer often uses both.
In our work
Our trailers are designed to read without sound, and we agree captions and languages with you in the proposal.
What to caption
Everything that is spoken, and any sound that changes the meaning. If the trailer has narration, caption it. If it has only music, the on-screen lines are the captions.
Languages
Captions are an easy way to reach readers in another language. A second set of captions lets one trailer serve more than one market.
Common mistakes
Lines too long for a phone, text over a busy image, and captions that arrive after the sound they describe.