FLUX 3 Image is on BFL's pricing page: which FLUX ids can Sume call?

Black Forest Labs' pricing page, read on 2026-10-07, lists FLUX 3 Image next to FLUX.2 [pro], [flex], [max] and [klein] 4B and 9B. Sume's image catalog lists two of those families: black-forest-labs/flux.2-pro and black-forest-labs/flux.2-flex. FLUX 3 Image, FLUX.2 [max] and FLUX.2 [klein] are not in Sume's catalog, so a request for one of them returns 404 model_not_found rather than falling back to something similar.

If you are choosing between FLUX 2 and FLUX 3 for a Sume integration, the answer today is FLUX.2 Pro for a default and FLUX.2 Flex when you want the second tier, and you keep the FLUX 3 comparison for the day it appears in GET /v1/images/models. Nothing in this post is a quality claim about FLUX 3; the only facts used are what each page lists.

The two lists side by side

The left column comes from BFL's pricing page. The right column comes from Sume's Image API docs and catalog. The prices are Sume's billed amounts, which are provider list times 1.25: FLUX.2 Pro lists at $0.03 per image, so $0.0375 billed, and FLUX.2 Flex lists at $0.05, so $0.0625 billed.

What the BFL page does and does not give you

The pricing page shows a calculator with figures such as $0.048 and $0.024 per image depending on the model and resolution you pick, but it does not lay out a per-model price table you can quote without driving the calculator. For that reason this post does not put a FLUX 3 price next to the Sume prices. If you need the vendor figure for a budget, open the page and read it for your resolution, then compare it to the billed column above.

The page also lists FLUX 3 Video and FLUX 3 Action in its footer navigation. Those are not image models, and Sume's image API does not list them either.

What FLUX.2 on Sume accepts

Both FLUX.2 ids list 13 aspect ratios: 1:1, 16:9, 9:16, 4:3, 3:4, 4:5, 5:4, 3:2, 2:3, 21:9, 9:21, 1:2 and 2:1. Both accept input_references for edits and up to 4 images per call. Custom pixels go on image_size as width and height. Neither lists a resolution tier, a quality tier, seed or mask_url, and Sume rejects a parameter that a model does not list with 400 unsupported_parameter. If you port a BFL request that carries other fields, strip them first.

Check the live catalog instead of trusting a blog post

Catalogs change, and this table is a dated snapshot. The one-line check below lists every image id Sume serves and keeps only the FLUX rows. If it prints something beyond black-forest-labs/flux.2-pro and black-forest-labs/flux.2-flex, the table above is stale and the catalog wins.

Run it in CI as well as by hand. A pinned id that disappears from the list is a much cheaper failure at deploy time than a 404 in front of a customer.

curl -s https://api.sume.com/v1/images/models \
  -H "Authorization: Bearer $SUME_API_KEY" | jq -r '.data[].id' | grep -i flux

How to be ready when a FLUX 3 id arrives

Keep the model id in config, and let your startup check read GET /v1/images/models and fail loudly when a pinned id is missing. When a FLUX 3 row appears, its supported_parameters will tell you which ratios, references and sizes it takes, and its /endpoints record will give the per-image billable line. Run your regression prompts against both ids at the same ratio before you switch. Until then, FLUX.2 Pro at $0.0375 billed is the cheaper of the two FLUX rows Sume offers, at 60 percent of Flex's $0.0625.

Keep in mind that every figure here is a billed price from Sume's catalog on the date in the table caption. Prices and limits can change, so before a large run, read the endpoint record for the exact model id and compare it with your plan. A one-minute check costs nothing, and it is the only way to be sure the number in your budget is the number on the invoice.