Glossary

YouTube glossary

The YouTube and thumbnail terms you’ll come across — explained in plain English, with what they mean for your thumbnails.

A YouTube thumbnail is the small preview image viewers see before clicking a video.

Impressions click-through rate is the share of thumbnail impressions that turned into views.

An impression is counted when a video’s thumbnail is shown to a viewer on YouTube.

Watch time is the total amount of time viewers have spent watching your videos.

Audience retention shows how much of a video viewers watch before leaving.

Clickbait is a thumbnail or title that promises something the video doesn’t deliver.

Thumbnail A/B testing compares two or more thumbnails to see which performs better.

Aspect ratio is the proportion of an image’s width to its height, such as 16:9.

The safe zone is the area of a thumbnail that won’t be covered by YouTube’s overlays.

The YouTube algorithm is the system that decides which videos to recommend to each viewer.

A hook is the idea that grabs attention and makes someone want to watch.

YouTube SEO is optimising videos so they’re found in YouTube search and recommendations.

Make your next thumbnail in minutes

Tell the AI agent what your video is about — it proposes a thumbnail, you approve it, and you can tweak it by asking.