Performance Max logo assets: 1200x1200 square and 1200x300 landscape

Performance Max wants two logo shapes: a square 1:1 logo recommended at 1200x1200 pixels (minimum 128x128) and a landscape 4:1 logo recommended at 1200x300. Both ratios are on Sume's image aspect-ratio list, but an image model should adapt your existing logo, not invent a new one.

The logo requirements

These values come from the Google Ads API page on Performance Max asset requirements, read on 2026-10-03.

File formats

The page lists GIF, JPG and PNG as accepted image formats. A logo with a transparent background should be a PNG, because JPG has no alpha channel and would put a solid box behind the mark on any colored placement.

What an image model should and should not do

A generative model is poor at reproducing an exact wordmark from a text description, and a brand mark that drifts between assets undermines the point of a logo. The safer routes:

• Export the square and landscape logos from your design files whenever you have them.
• Use Sume only for derivative work: extending a background, producing a clean padded canvas, or making a transparent-background variant from a reference.
• Pass the real logo as an input_references entry and ask for it unchanged, then compare the output to the original at full size.
• Never ship a logo you have not looked at pixel by pixel; a single dropped letter is easy to miss at thumbnail size.

Ratios and transparency on Sume

The Image API lists 1:1 and 4:1 among its normalized aspect ratios, and a given model accepts only the subset in its catalog descriptors. background: transparent is documented for ChatGPT Image 2.5, and output_format can be png. ChatGPT Image 2.5 takes up to 16 image references and its image_size accepts custom pixels where both edges are multiples of 16, with a maximum edge of 3840 and aspect ratio at most 3:1.

That last limit matters here: a 4:1 canvas is wider than 3:1, so check the model's descriptor before assuming a native 1200x300 output. If a model rejects it, generate the nearest accepted ratio and pad or crop to 4:1 in your own tooling.

{
  "model": "openai/gpt-image-2.5",
  "prompt": "Keep the logo exactly as in the reference, centered, transparent background, no extra elements",
  "input_references": [
    { "type": "image_url", "image_url": { "url": "https://example.com/logo.png" } }
  ],
  "background": "transparent",
  "output_format": "png",
  "aspect_ratio": "1:1"
}

Final checks

Before upload, confirm the pixel size is at least 128x128 for the square logo, that the landscape file is a true 4:1 shape, and that the mark stays legible when displayed small on a dark and a light background.