Choosing a caption font that stays readable

Captions get read on a six inch screen, often with the sound off, while the viewer decides in a second whether to keep scrolling. The font you pick sets the tone of the video, but legibility at that size decides whether anyone reads it at all.

Match the family to the job

• Display fonts like luckiest-guy or dynapuff fit high energy shorts where the caption is part of the show. They carry bold outlines well.
• Sans-serifs like inter, roboto or fredoka are the quiet workhorses for tutorials and talking-head clips, where the words matter more than the styling.
• Serifs and slabs like merriweather or arvo suit calmer, editorial content: essays on video, readings, slower podcasts.
• Script fonts like story-script are accents. A full video in script is a reading test nobody asked for.

Thin strokes need help

Script and handwriting fonts have thin strokes that disappear at small sizes. If you use one, go up a size and give the text a solid base: the backdrop decoration or a bold text color keeps the strokes readable. Display fonts are the opposite, they shine with the default outline.

curl -X POST https://api.caption.sh/v1/videos \
  -H "Authorization: Bearer $CAPTION_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"source_url":"https://cdn.example.com/clip.mp4","options":{"font":"inter","size":"large"}}'

The renderer covers the edge cases

A wide font plus a long word is where caption layouts usually break. caption.sh lays every group out inside a 90 percent width margin and shrinks the text until it fits the line limit, so an unexpected word never overflows the frame, whichever of the 18 bundled fonts you pick. All of them are open source and free to burn into video.

The full font list with keys, plus the decoration and size options, is at caption.sh/docs.