4:5, 9:16 and 16:9 together: 15 of 19 Sume image models list all three

Fifteen of the 19 Sume image models list 4:5, 9:16 and 16:9 together, so one model can cover an Instagram feed post, a Story and a YouTube thumbnail. The four that miss 4:5 are Higgsfield Soul, Grok Imagine, Imagen 4 Fast and Imagen 4 Ultra. Every model lists 9:16 and 16:9.

The 15 that cover all three

Pass aspect_ratio in the request, for example 4:5 for a portrait feed post. 4:5 is Instagram portrait (1080x1350). Nano Banana Pro sends 4:5 natively at about 928x1152 at 1K, and exact 1080x1350 comes from a documented post-step through job target_pixels.

The four that miss 4:5

These models list 9:16 and 16:9, so a vertical Story or a wide thumbnail works, but a 4:5 request returns 400 unsupported_parameter. The nearest substitute is 3:4, which Imagen lists, or 2:3, which Soul and Grok list.

Grok Imagine adds the phone ratios 9:19.5 and 9:20, which no other model lists.

Practical pick

If one model has to serve three placements, the cheapest full-coverage row is Qwen Image, which lists all three and bills 3 cents. At 5 cents Seedream 5.0 Lite adds image editing. Set the ratio per request, never rely on a crop, and confirm with the live descriptor from GET /v1/images/models.

Edge cases to know

Ratio support is per model, and a request that sets a value the model does not list is rejected with 400 unsupported_parameter rather than adjusted. On edit calls, aspect_ratio: auto matches the reference image, and leaving the field out is not equivalent. Always read supported_parameters from the catalog before you pin a tier or ratio.

For a three-placement campaign, one prompt at three ratios costs 9 cents on Qwen Image, 12 on Flux 2 Pro, 15 on Seedream 5.0 Lite and 21 on GPT Image 2.5 at high. A set of 50 products is therefore $4.50, $6.00, $7.50 or $10.50. Pick the row, then pin the three ratios in code so a copy-paste never sends a ratio the row does not list.