The most popular AdSense ad quality isn’t the best for revenue and user experience; However, they often have the most competition for advertisers for placement. These include:
- 336 x 280 large rectangle
- 300 x 250 medium rectangle
- 728 x 90 leaderboard
- 300 x 600 half page
- 320 x 100 large mobile banner
Research presented by Google shows that offering fewer ads can increase revenue, but only if it is done with data, not personal opinion. Display text and image media. Limiting ad types to one type can reduce competition for a single ad placement.
Do not disguise ads. Keep ads looking like ads. Being deceptive about where ads are placed (i.e. close to buttons and navigation) will generate false clicks; which can lead to you getting banned.