Call to action

A banner without a prompt gets looked at; a banner with a prompt gets clicked. The call to action says what happens after the click and looks like a button, even though technically the whole creative is clickable. Good CTAs start with a verb, promise something specific and stay under three words.

The button needs the most striking colour in the banner and enough space around it. In a leaderboard it sits on the right, in portrait sizes at the bottom, always as the last element in reading order. Digital out-of-home works without a CTA; there a short URL replaces the click.