Runway image API: Seedream 5 Lite at $0.04 vs Sume's $0.04375

Runway's API page lists seedream5_lite at 4 credits per image, $0.04 at $0.01 a credit. Sume lists seedream-5-lite at $0.04375, 9.4 percent higher ($0.00375 per image). For 500 images that is $20.00 against $21.875.

Image rows side by side

Runway's page gives per-image credit rates. Sume's rates are from its price list, which is the provider list times 1.25.

What this means

Runway's own image models are Runway-only, and Sume does not list them. The only same-name row is Seedream 5 Lite. On that row Runway is cheaper by 9.4 percent. If your need is the cheapest possible draft image from Sume, the answer is gpt-image-2.5 on low at $0.02475, with grok-image and imagen-4-fast at $0.025.

• 500 Seedream 5 Lite images: $20.00 on Runway, $21.875 on Sume.
• 500 GPT Image 2.5 low images on Sume: $12.375.
• 500 flux-2-pro images on Sume: $18.75 at $0.0375 each.

Calling the Sume row

Seedream 5 Lite goes through the Images API like any catalog id.

curl -X POST https://api.sume.com/v1/images \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: seedream-5-lite-draft" \
  -d '{
    "model": "seedream-5-lite",
    "prompt": "Minimal poster of a paper boat on calm water",
    "aspect_ratio": "3:4",
    "n": 4
  }'

Caveat

A shared name is not proof of shared limits. Runway's page does not list image sizes for seedream5_lite in the part read here, and Sume prices it flat. Compare the output sizes you need before you treat the two prices as equal.

A 2,000-image month

At 2,000 Seedream 5 Lite images a month, Runway is 2,000 x $0.04 = $80.00 and Sume is 2,000 x $0.04375 = $87.50, a gap of $7.50. If the same month is drafts on Sume's GPT Image 2.5 low row, it is 2,000 x $0.02475 = $49.50. That is a different model, so the saving is only real if the draft quality is enough for the job.

Runway's page also lists a credit price per image for gen4_image at two sizes, 5 credits at 720p and 8 at 1080p. Those are Runway-only models and have no Sume row to compare.