Free tool
Aspect Ratio Calculator
Pick a target ratio (1:1, 4:5, 9:16, 16:9, 2.39:1) and instantly get the matching pixel dimensions for every popular model — Flux, SDXL, DALL·E and Midjourney.
Recommended dimensions
816 × 1024
Rounded to multiples of 8 (required by most diffusion models).