Google Merchant Center 16 MB and 64 megapixel image limits vs Sume

Google Merchant Center says no image larger than 64 megapixels and no image file larger than 16MB. Sume's openai/gpt-image-2.5 custom image_size tops out at 8,294,400 pixels, about 8.3 megapixels, so the pixel limit cannot be hit; the file size is not published, so measure it after download.

What does Google list?

From the page read on 2026-09-30: no image larger than 64 megapixels, and no image file larger than 16MB.

Why is the pixel limit safe?

The docs cap a custom image_size at a 3840 pixel edge and 8,294,400 total pixels, and 8,294,400 is 3840 x 2160. Google's 64 megapixel line is roughly eight times that.

How do I check the file size?

The docs list output_compression as not served in v1 and give no byte size for outputs. Download the file from the returned media.sume.com URL and read its size. If it is over 16 MB, request a smaller size or a different output_format (png, jpeg or webp, depending on the model's catalog entry).

URL="https://media.sume.com/img/demo/0.png"
curl -s -o product.png "$URL"
bytes=$(wc -c < product.png)
if [ "$bytes" -gt 16000000 ]; then
  echo "over 16 MB: request a smaller image_size or another output_format"
else
  echo "size ok: $bytes bytes"
fi

What does 16 MB mean in bytes?

Google writes 16MB and does not say whether it means 16,000,000 or 16,777,216 bytes, so the script above uses the lower one. Stay under it. Re-read Google's page before an upload.