For a fair A/B test, use the same prompt, aspect ratio and references. Inspect more than overall style: object preservation, geometry, faces and hands, fine detail, text in the frame and unintended changes during editing.
What to inspect with Nano Banana 2
Combine references into a scene and adapt it from a square post to a wide banner.
Create from text or edit from images; request 1, 2 or 4 results.
1K, 2K or 4K; 15 aspect-ratio options including Auto and very wide or tall formats.
Ten references is a ceiling, not a recommendation for every task.
More pixels do not fix mixed-up characters or incorrect product geometry.
What to inspect with Seedream 5.5
Create and edit images at 1K, 1.5K and 2K with up to 10 input photos and eight aspect ratios.
From text alone, or editing with 1–10 input photos.
1K, 1.5K and 2K; ratios 1:1, 4:3, 3:4, 16:9, 9:16, 2:3, 3:2 and 21:9.
This model has no 4K size: the maximum is 2K.
References do not guarantee exact text, logos or fine details, so check them in the result.
How to run a fair comparison
Give both models one prompt, one aspect ratio and, for editing tests, the same source photo.
Look at the small things: hands, small text, product edges and logos fail differently in every model.
Generate at least three variants per model: one picture shows one seed, not the usual quality.
Compare cost at the resolution you will actually publish, not at each model's cheapest setting.
Sources
Prices, availability and specifications come from the Mixer AI catalog. This is not an independent test: try both models on the same task before choosing.
Price, 1 image · 1K: the prices of Nano Banana 2 and Seedream 5.5 are in the comparison table and always match the current tariff. The total depends on your settings: the price of the chosen options is shown in the interface before you run.
How does Nano Banana 2 differ from Seedream 5.5?
Nano Banana 2 — resolutions: 1K / 2K / 4K.
How should I compare Nano Banana 2 and Seedream 5.5 fairly?
Give both models the same prompt, aspect ratio and source photo, generate three variants each and compare details: hands, text, object edges. Compare price at the resolution you will publish.
Are both models available in Mixer AI?
Yes. Both models are in the Mixer AI image catalog; the launch button on the page opens Canvas on a computer and the Studio on a phone. The page exists only for models in the current catalog.
Which model is better?
There is no single winner. First rule out the model that does not accept the inputs you need (references, editing) or the resolution you need, then compare results on your own task. The table highlights only measurable differences.