21:9 aspect ratio (21:9)
21:9 is the anamorphic cinema ratio. It produces dramatic panoramas and fits ultrawide monitors exactly.
Standard pixel sizes
| Size string | Resolution | Megapixels |
|---|---|---|
| 2560×1080 | 2560 × 1080 px | 2.76 MP |
| 3440×1440 | 3440 × 1440 px | 4.95 MP |
Need a custom fit? The aspect ratio calculator fits this ratio into any megapixel budget.
What to use 21:9 for
Ultrawide wallpapers, cinematic letterboxing, panorama-style heroes and banner ads.
Models that support 21:9
21:9 FAQ
What resolution is 21:9?
21:9 is a ratio, not a fixed resolution — any pixel dimensions where width ÷ height = 21 ÷ 9 is "21:9". Common generation sizes include 2560×1080, 3440×1440, listed in the table above.
Which AI models generate 21:9 images?
Most image generation models on our gateway cover the common ratios; check each model's spec sheet for the full list.
Which AI video models output 21:9?
Seedance 2.0 Fast, Seedance 2.0 Mini, HappyHorse 1.1, HappyHorse 1.0 generate 21:9 video. Video on our gateway is limited to 16:9 and 9:16.
How much does a 21:9 generation cost?
Aspect ratio doesn't affect price — image models bill per generated image (from $0.025) and video models per clip. See the pricing page for live rates.