There is no single “best” banner size, but there are a few dependable ones. For a full-width hero, 1920 × 1080 (16:9) is the safe default that scales cleanly from 4K down to mobile.
Common website banner sizes
- Hero: 1920 × 1080 (16:9)
- Wide strip: 1920 × 600
- Blog / OG card: 1200 × 628
- Sidebar: 300 × 250
Whatever size your theme needs, add it as a custom preset in BannerCrop AI and export in seconds.