Image prices with fractions of a cent on Sume: $0.04375, $0.09375

Sume's image prices are not whole cents on every row. Endpoint pricing is the provider list rate multiplied by the Sume margin of 1.25, so Seedream 5.0 Lite shows $0.04375 per image and Qwen Image Max shows $0.09375. You are charged cost_usd x n for a completed call. Four Seedream 5.0 Lite images are 4 x $0.04375 = $0.175, and 1,000 of them are $43.75.

Where the fraction comes from

The Image API docs say endpoint pricing lines are the amount Sume charges to your wallet and that those lines already include the Sume margin. In the catalog code the published price is the list price in micro dollars times 125 over 100, rounded up to the next micro dollar. Seedream 5.0 Lite lists at 35,000 micro dollars ($0.035), and 35,000 x 1.25 = 43,750 micro dollars, which is $0.04375 exactly. Nothing rounds to cents.

Compute it, do not eyeball it

Use decimal arithmetic. Floating point turns $0.04375 x 3 into a long tail, and a budget guard that compares floats can fail on an exact limit.

from decimal import Decimal as D

list_price = {"seedream-5-lite": D("0.035"), "flux-2-pro": D("0.03")}
for name, p in list_price.items():
    each = p * D("1.25")
    print(name, each, "x4 =", each * 4)

What the number does not cover

Static rows have one price per image. GPT Image 2.5 and GPT Image 2 are billed from image tokens, so quality and size move the price, and the catalog row only shows a high 1024 display rate. Nano Banana rows list a 1K rate and scale it for other tiers.

Failed and cancelled generations are not billed. A call that completes is billed in full. So the fractions only matter in aggregate: at 1,000 images the difference between Flux 2 Pro ($37.50) and Seedream 5.0 Lite ($43.75) is $6.25.

Check live prices

Rates change. Read the pricing line from GET /v1/images/models/{model_id}/endpoints before a large run, and compare it with your own table.

curl https://api.sume.com/v1/images/models/bytedance-seed/seedream-5-lite/endpoints \
  -H "Authorization: Bearer $SUME_API_KEY"

Budget guards and displays

If your app shows a price, show it with the digits the API returns rather than rounding to cents. Rounding $0.04375 up to $0.05 overstates a 1,000 image run by $6.25, and rounding down to $0.04 understates it by $3.75.

If you set a spending cap, compare it with the exact product of cost_usd and n using decimals. A cap of $0.175 admits four Seedream 5.0 Lite images exactly, and a cap of $0.17 does not.

• Four images at $0.04375 = $0.175.
• Eight images at $0.0375 (Flux 2 Pro) = $0.30.
• Ten images at $0.09375 (Qwen Image Max) = $0.9375.