100 game icons at 512px on Nano Banana 2.1: $7.50 on Sume

A hundred 1:1 game icons at 512 pixels on google/nano-banana-2.1 cost about $7.50 on Sume: resolution: "0.5K" bills about $0.075 an image. The value 512 is accepted as an alias for 0.5K, so either spelling works. Google made Nano Banana 2.1 generally available on October 6, 2026, and its changelog notes the model keeps character consistency across turns, which is what an icon set needs.

Most icon packs need a shared look more than raw quality. This post covers a workable process and where the money goes.

Budget at each tier

Make the set consistent

• Write one style paragraph and reuse it verbatim: material, outline, lighting, palette and background color.
• Generate one anchor icon you like and pass it as input_references for every other icon, so the style carries over. Up to 10 references are allowed.
• Fix the ratio at 1:1 and the resolution at 0.5K for the whole set so the files line up.
• Put only the item name in the variable part of the prompt, for example 'iron sword', 'healing potion'.

Example request

Send one request per icon with the anchor image as a reference:

{
  "model": "google/nano-banana-2.1",
  "prompt": "Match image 1 exactly in style. New icon: healing potion, centered, plain background",
  "aspect_ratio": "1:1",
  "resolution": "0.5K",
  "input_references": [
    {"type": "image_url", "image_url": {"url": "https://example.com/anchor-sword.png"}}
  ]
}

Fixing the misses

Expect some misses. If one icon in ten needs a retry, add $0.75 to the $7.50 total, and failed generations are not billed. Upscale only the winners: rerunning an icon at 2K costs $0.15, which is cheaper than redoing the whole set at 2K ($15.00).

Keep a spreadsheet of prompt, file name and usage.cost so that the final cost matches your plan.

Using the output

Keep the files named by item, not by number, so a designer can find 'healing-potion' without opening the folder. Hosted result URLs are for download and handoff, so copy the files into your own storage before you ship, and record the usage.cost per file next to the name.

Test the set at actual size. A 512px icon shown at 64px hides detail you paid for, so check that outlines survive the shrink before you commit to a final tier.

Where the 512px size fits

At 0.5K the file is small enough to preview in a review tool without scrolling, which makes a 100-icon contact sheet practical. Make the contact sheet before you pick the winners; a style drift that is easy to see in a grid is hard to see one file at a time.

If the game engine wants power-of-two textures, resize the approved files yourself, because the API returns the sizes it lists, not a texture atlas.

What Sume does not do

Sume does not guarantee that two icons share a style, and it does not expose a seed for reproducing one. It also does not cut out the background; for transparent stills, the docs point to Image 1.0 with transparency: true, or you remove the background in your own pipeline.