FLUX.2 is Black Forest Labs' high-fidelity image family, known for strong prompt adherence and unusually crisp in-image text. On HiAPI it comes in three tiers across two modes — text-to-image and image-to-image — and every call is billed per image, with no subscription and no per-token math. This guide breaks down the real 2026 numbers (re-checked against HiAPI's live pricing on 2026-10-16), shows what the price gap actually looks like with the same prompt, and explains how to start.
FLUX.2 API pricing at a glance (2026)
All figures are per image, in USD. See live pricing for the current numbers.
Text-to-image
| Model | 0.25 MP | 0.5 MP | 1 MP | 2 MP | 4 MP |
|---|---|---|---|---|---|
| FLUX.2 Pro | — | $0.0375 | $0.05 | $0.075 | $0.125 |
| FLUX.2 klein 4B | $0.00036 | $0.00072 | $0.00143 | $0.00286 | $0.00572 |
FLUX.2 klein 9B text-to-image is a flat $0.00858 per image at any resolution (it runs a fixed four-step pipeline), so it sits between the two tiers above.
Image-to-image (editing)
| Model | Price per image | Notes |
|---|---|---|
| FLUX.2 Pro | $0.035 (1K) · $0.05 (2K) | up to 8 reference images |
| FLUX.2 klein 9B | $0.03143 (flat) | one reference image |
| FLUX.2 klein 4B | $0.00608 (0.25 MP) → $0.01143 (4 MP) | one reference image; $0.00715 at 1 MP |
The three FLUX.2 tiers, and who each is for
FLUX.2 Pro is the flagship: best prompt adherence, finest detail, and the most reliable in-image text, at $0.05 for a standard 1 MP image. Reach for it on hero shots, client deliverables, and anything with text a reader will actually scrutinise. See the FLUX.2 Pro model page.
FLUX.2 klein 9B is the balanced middle — a fast four-step model at a flat $0.00858 per image, roughly 6× cheaper than Pro for text-to-image, with strong realism for everyday work. See FLUX.2 klein 9B.
FLUX.2 klein 4B is the volume and draft tier, from $0.00036 per image. It is compact and fast — ideal for ideation, A/B batches, thumbnails, and high-volume pipelines where cost per image matters more than the last few percent of fidelity. See FLUX.2 klein 4B.
How resolution changes the price
Pro and klein 4B price by output size; klein 9B does not.
- On Pro, moving from 0.5 MP ($0.0375) to 4 MP ($0.125) is a 3.3× jump. The 1 MP tier ($0.05) is the sweet spot for most web and social work.
- On klein 4B, the same 0.25 → 4 MP climb runs $0.00036 → $0.00572 (about 16×), yet even the top tier stays cheaper than Pro's smallest.
- klein 9B ignores resolution entirely, which makes per-image budgeting dead simple.
Practical tip: lock your prompt at a low tier, then re-run only the keeper at higher resolution. You pay cents to explore and the full price just once.
Text-to-image vs image-to-image
Editing is priced separately from generating, and the gap is not uniform across tiers:
- Pro editing is actually cheaper than its own generation at comparable size — $0.035 at 1K versus $0.05 at 1 MP — and it accepts up to 8 reference images for multi-image composition.
- klein 9B is the catch. Its editing is a flat $0.03143, nearly 4× its own text-to-image price and within a rounding error of Pro's 1K edit ($0.035). If your workload is mostly editing, klein 9B's discount largely disappears, so compare it against Pro directly.
- klein 4B editing runs $0.00608–$0.01143 by resolution ($0.00715 at 1 MP) — still the cheapest way to batch-edit.
What the price actually buys: one prompt, two tiers
To make the gap concrete, I ran the same prompt through klein 4B and Pro, both at 1 MP. The difference lands exactly where you would expect: fine detail and text.
A matte charcoal coffee bag standing on a rustic oak counter, warm morning window light, shallow depth of field, a clean minimalist kraft paper label on the bag reading 'DAYBREAK ROAST', fine fabric and paper texture, soft steam rising, premium commercial product photography, 50mm lens
Both are usable product shots. But klein 4B dropped a letter — "DAYBREEK" instead of "DAYBREAK" — while Pro rendered the label cleanly and held crisper texture in the foil and kraft paper. That single misspelling is the whole pricing argument in miniature: for moodboards and volume, the $0.00143 image is plenty; for anything a customer will read, the $0.05 image earns its keep.
What $1 and $10 buy
Straight from the per-image prices above (text-to-image):
| Model & tier | Per image | Images per $1 | Images per $10 |
|---|---|---|---|
| klein 4B · 0.25 MP | $0.00036 | ~2,777 | ~27,700 |
| klein 4B · 1 MP | $0.00143 | ~699 | ~6,990 |
| klein 9B · flat | $0.00858 | ~116 | ~1,165 |
| Pro · 1 MP | $0.05 | 20 | 200 |
| Pro · 4 MP | $0.125 | 8 | 80 |
How to access FLUX.2 on HiAPI
One API key covers all three tiers. Image models run on an async task endpoint:
- Sign up and grab your key. New accounts start with free credits; billing is pay-as-you-go with no minimum, and failed tasks are not charged.
POST /v1/taskswith a body like{"model": "flux-2/text-to-image", "input": {"prompt": "...", "aspect_ratio": "16:9", "resolution": "1 MP"}}and you receive ataskId.- Poll
GET /v1/tasks/{taskId}untilstatusissuccess, then downloadoutput[0].url.
Full parameters and copy-paste code live in the FLUX.2 text-to-image API guide and the HiAPI docs.
FAQ
How much does the FLUX.2 API cost? Per image on HiAPI: FLUX.2 Pro is $0.05 at 1 MP (up to $0.125 at 4 MP), klein 9B is a flat $0.00858, and klein 4B starts at $0.00036. Image editing is priced separately.
Which FLUX.2 model is the cheapest? klein 4B. A 0.25 MP image is $0.00036 — under a twentieth of a cent — and even 4 MP is only $0.00572.
Does resolution change the price? Yes for Pro and klein 4B, which bill by megapixels. klein 9B is flat regardless of output size.
Is image-to-image more expensive than text-to-image? It depends on the tier. On Pro, a 1K edit ($0.035) is cheaper than a 1 MP generation ($0.05). On klein 9B, editing ($0.03143) costs far more than generating ($0.00858). On klein 4B, editing adds roughly half a cent.
Is FLUX.2 good at in-image text? Pro is reliably good — in our test it rendered the label correctly. The cheaper klein tiers can drop or garble letters, so reserve Pro for text you cannot afford to get wrong.
Takeaways
For volume and drafts, klein 4B is hard to beat — hundreds to thousands of images per dollar. For client-facing work with readable text, pay for Pro. Watch klein 9B's editing price, which lands close to Pro's. And always explore cheap before you render expensive.
Ready to try it? Start with klein 4B to explore ideas for cents, then switch to Pro for the final render — browse the full FLUX.2 lineup on HiAPI and ship your first image today.
