How many reference images can FLUX.2 use?

FLUX.2 Pro, Max, and Flex each accept up to 8 reference images as publicly accessible URLs or Base64. Output plus all reference images must stay within 9 MP.

Which FLUX.2 variant should I choose?

Choose Pro for balanced speed, quality, and cost, Max when the highest output quality matters most, and Flex when you need adjustable steps, guidance, or stronger layout control.

Can every FLUX.2 model adjust steps and guidance?

No. These controls are exclusive to flux-2-flex: steps accepts 1–50 and guidance accepts 1.5–10. Pro and Max do not expose them.

What output sizes and formats are supported?

Use 1MP, 2MP, 3MP, or 4MP with any of 9 ratios, or provide width and height of at least 64 px with a total output limit of 4 MP. Formats are PNG, JPEG, and WebP.

How does the asynchronous API work?

POST /v1/images/generations returns a task ID. Poll GET /v1/tasks/{task_id} until the task is completed or failed; each task returns one image.

How is FLUX.2 priced, and what happens if a task fails?

The charge depends on the selected output tier or exact dimensions and the number of reference images. Use the completed task's cost field as the source of truth. Failed tasks are automatically refunded in full.

Is there a discount on the FLUX.2 API?

Yes. Prices shown on this page are Gold member prices, already 20% off. Platinum and Diamond members save even more, up to 28%, and you only pay for successful requests.

How much does each FLUX.2 model cost per image?

Original prices on APIMart (October 2026) for a 2MP output: FLUX.2 Pro $0.045, FLUX.2 Flex $0.10 and FLUX.2 Max $0.10. Output from 1MP to 4MP costs $0.03–$0.075 on Pro, $0.05–$0.20 on Flex and $0.07–$0.16 on Max, and each reference image adds a charge by its own megapixel tier. Gold members pay 20% less and Platinum and Diamond members save up to 28%; see each model page for its full table.

How do I get a FLUX.2 API key?

Sign up for APIMart, open the API Keys page in your dashboard and create a new key. The same key calls the Black Forest Labs FLUX.2 API and every other model on the platform, with pay-as-you-go billing and no subscription.

Is the Flux 2 API the same as the FLUX.2 API?

Yes. Flux 2 is a common way to write FLUX.2, Black Forest Labs' image family with Pro, Max and Flex variants. On APIMart, call the Flux 2 API by setting model to flux-2-pro, flux-2-max or flux-2-flex. FLUX.1 Kontext (flux-kontext-pro and flux-kontext-max) is also available with the same API key.

FLUX.2 API: Pro, Max & Flex Pricing and Editing

Output image

Output billing uses the 1MP, 2MP, 3MP, and 4MP tiers.

Output image. Output billing uses the 1MP, 2MP, 3MP, and 4MP tiers.
Variant	Tier	GoldCurrent price	Platinum	Diamond	Official	Your savings
`flux-2-pro`	1MP	0.24Credits(~$0.024)	0.228Credits(~$0.0228)	0.216Credits(~$0.0216)	0.3Credits(~$0.03)	20%
	2MP	0.36Credits(~$0.036)	0.342Credits(~$0.0342)	0.324Credits(~$0.0324)	0.45Credits(~$0.045)	20%
	3MP	0.48Credits(~$0.048)	0.456Credits(~$0.0456)	0.432Credits(~$0.0432)	0.6Credits(~$0.06)	20%
	4MP	0.6Credits(~$0.06)	0.57Credits(~$0.057)	0.54Credits(~$0.054)	0.75Credits(~$0.075)	20%
`flux-2-max`	1MP	0.56Credits(~$0.056)	0.532Credits(~$0.0532)	0.504Credits(~$0.0504)	0.7Credits(~$0.07)	20%
	2MP	0.8Credits(~$0.08)	0.76Credits(~$0.076)	0.72Credits(~$0.072)	1Credits(~$0.1)	20%
	3MP	1.04Credits(~$0.104)	0.988Credits(~$0.0988)	0.936Credits(~$0.0936)	1.3Credits(~$0.13)	20%
	4MP	1.28Credits(~$0.128)	1.216Credits(~$0.1216)	1.152Credits(~$0.1152)	1.6Credits(~$0.16)	20%
`flux-2-flex`	1MP	0.4Credits(~$0.04)	0.38Credits(~$0.038)	0.36Credits(~$0.036)	0.5Credits(~$0.05)	20%
	2MP	0.8Credits(~$0.08)	0.76Credits(~$0.076)	0.72Credits(~$0.072)	1Credits(~$0.1)	20%
	3MP	1.2Credits(~$0.12)	1.14Credits(~$0.114)	1.08Credits(~$0.108)	1.5Credits(~$0.15)	20%
	4MP	1.6Credits(~$0.16)	1.52Credits(~$0.152)	1.44Credits(~$0.144)	2Credits(~$0.2)	20%

Reference images

A single reference image uses its actual pixel tier, up to 4MP. With two or more images, each is billed at 1MP.

Reference images. A single reference image uses its actual pixel tier, up to 4MP. With two or more images, each is billed at 1MP.
Variant	Tier	GoldCurrent price	Platinum	Diamond	Official	Your savings
`flux-2-pro`	1MP	0.12Credits(~$0.012)	0.114Credits(~$0.0114)	0.108Credits(~$0.0108)	0.15Credits(~$0.015)	20%
	2MP	0.24Credits(~$0.024)	0.228Credits(~$0.0228)	0.216Credits(~$0.0216)	0.3Credits(~$0.03)	20%
	3MP	0.36Credits(~$0.036)	0.342Credits(~$0.0342)	0.324Credits(~$0.0324)	0.45Credits(~$0.045)	20%
	4MP	0.48Credits(~$0.048)	0.456Credits(~$0.0456)	0.432Credits(~$0.0432)	0.6Credits(~$0.06)	20%
`flux-2-max`	1MP	0.24Credits(~$0.024)	0.228Credits(~$0.0228)	0.216Credits(~$0.0216)	0.3Credits(~$0.03)	20%
	2MP	0.48Credits(~$0.048)	0.456Credits(~$0.0456)	0.432Credits(~$0.0432)	0.6Credits(~$0.06)	20%
	3MP	0.72Credits(~$0.072)	0.684Credits(~$0.0684)	0.648Credits(~$0.0648)	0.9Credits(~$0.09)	20%
	4MP	0.96Credits(~$0.096)	0.912Credits(~$0.0912)	0.864Credits(~$0.0864)	1.2Credits(~$0.12)	20%
`flux-2-flex`	1MP	0.4Credits(~$0.04)	0.38Credits(~$0.038)	0.36Credits(~$0.036)	0.5Credits(~$0.05)	20%
	2MP	0.8Credits(~$0.08)	0.76Credits(~$0.076)	0.72Credits(~$0.072)	1Credits(~$0.1)	20%
	3MP	1.2Credits(~$0.12)	1.14Credits(~$0.114)	1.08Credits(~$0.108)	1.5Credits(~$0.15)	20%
	4MP	1.6Credits(~$0.16)	1.52Credits(~$0.152)	1.44Credits(~$0.144)	2Credits(~$0.2)	20%

curl -X POST https://api.apimart.ai/v1/images/generations \ -H "Authorization: Bearer $APIMART_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "model": "flux-2-pro", "prompt": "A minimalist skincare product on a travertine stone, soft side light, clean beige background, studio product photo", "resolution": "2MP", "size": "16:9", "output_format": "jpeg" }'

import os import time import requests API_BASE = "https://api.apimart.ai" headers = {"Authorization": f"Bearer {os.environ['APIMART_API_KEY']}"} # 1. Submit the generation task payload = { "model": "flux-2-pro", "prompt": "A minimalist skincare product on a travertine stone, soft side light, clean beige background, studio product photo", "resolution": "2MP", "size": "16:9", "output_format": "jpeg" } resp = requests.post(f"{API_BASE}/v1/images/generations", headers=headers, json=payload, timeout=60) resp.raise_for_status() task_id = resp.json()["data"][0]["task_id"] # 2. Poll the task until it finishes for _ in range(200): task_resp = requests.get(f"{API_BASE}/v1/tasks/{task_id}", headers=headers, timeout=30) task_resp.raise_for_status() task = task_resp.json()["data"] if task["status"] == "completed": print(task["result"]["images"][0]["url"][0]) break if task["status"] == "failed": raise RuntimeError(task.get("error", {}).get("message", "generation failed")) time.sleep(3) else: raise TimeoutError(f"task {task_id} did not finish in time; continue GET polling with this task ID")

curl -X POST https://api.apimart.ai/v1/images/generations \ -H "Authorization: Bearer $APIMART_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "model": "flux-2-pro", "prompt": "Place the product from the reference image on a marble bathroom shelf and match the warm lighting", "resolution": "2MP", "size": "auto", "image_urls": [ "https://example.com/reference.jpg" ] }'

Parameter	Type	Required	Default	Description
`model`	string	Required	Default: flux-2-pro	flux-2-pro, flux-2-max or flux-2-flex.
`prompt`	string	Required	Default: —	Describe the image to generate or the edit to apply to the reference images.
`resolution`	string	Optional	Default: 2MP	1MP, 2MP, 3MP or 4MP output tier.
`size`	string	Optional	Default: 1:1	1:1, 4:3, 3:4, 16:9, 9:16, 3:2, 2:3, 21:9, 9:21, auto (follow the reference) or a pixel string such as 1024x1536.
`width`	integer	Optional	Default: —	Exact width in pixels, at least 64. Send together with height; the pair overrides resolution and size.
`height`	integer	Optional	Default: —	Exact height in pixels, at least 64. width × height must not exceed 4 MP.
`image_urls`	string[]	Optional	Default: —	Up to 8 reference images as public URLs or Base64. Output plus all references must stay within 9 MP.
`output_format`	string	Optional	Default: jpeg	jpeg, png or webp.
`seed`	integer	Optional	Default: —	Reuse the same seed and parameters for reproducible output; omit for a random seed.
`prompt_upsampling`	boolean	Optional	Default: false	Let the model enhance and rewrite the prompt before generation.
`safety_tolerance`	integer	Optional	Default: 2	0 (strictest) to 5.
`nsfw_check`	boolean	Optional	Default: false	Review the prompt and input images with omni-moderation-latest before submission.
`steps`	integer	Optional	Default: 50	Sampling steps from 1 to 50; more steps add detail but take longer. Only flux-2-flex accepts it.
`guidance`	number	Optional	Default: 5.0	Prompt guidance from 1.5 to 10; higher values follow the prompt more closely. Only flux-2-flex accepts it.

Parameter

Type

Required

Default

Description

model

string

Required

Default: flux-2-pro

flux-2-pro, flux-2-max or flux-2-flex.

prompt

string

Required

Default: —

Describe the image to generate or the edit to apply to the reference images.

resolution

string

Optional

Default: 2MP

1MP, 2MP, 3MP or 4MP output tier.

size

string

Optional

Default: 1:1

1:1, 4:3, 3:4, 16:9, 9:16, 3:2, 2:3, 21:9, 9:21, auto (follow the reference) or a pixel string such as 1024x1536.

width

integer

Optional

Default: —

Exact width in pixels, at least 64. Send together with height; the pair overrides resolution and size.

height

integer

Optional

Default: —

Exact height in pixels, at least 64. width × height must not exceed 4 MP.

image_urls

string[]

Optional

Default: —

Up to 8 reference images as public URLs or Base64. Output plus all references must stay within 9 MP.

output_format

string

Optional

Default: jpeg

jpeg, png or webp.

seed

integer

Optional

Default: —

Reuse the same seed and parameters for reproducible output; omit for a random seed.

prompt_upsampling

boolean

Optional

Default: false

Let the model enhance and rewrite the prompt before generation.

safety_tolerance

integer

Optional

Default: 2

0 (strictest) to 5.

nsfw_check

boolean

Optional

Default: false

Review the prompt and input images with omni-moderation-latest before submission.

steps

integer

Optional

Default: 50

Sampling steps from 1 to 50; more steps add detail but take longer. Only flux-2-flex accepts it.

guidance

number

Optional

Default: 5.0

Prompt guidance from 1.5 to 10; higher values follow the prompt more closely. Only flux-2-flex accepts it.

Model	Best for	Output
FLUX 3 Image API	The FLUX 3 API for images: generation and editing with up to 10 references, search grounding and output up to 4K	768sq to 4K (about 16 MP)
FLUX 3 Image Klein API	Lower-cost FLUX 3 images with seed, 1–16 steps and PNG or JPEG output	768sq to 4K (about 16 MP)
FLUX 3 Video API	Text to video, 1–10 keyframes, video continuation and drafts, with synced audio	HD or FHD, 5–20 s
FLUX.2 APIThis page	Choosing between FLUX.2 Pro, Max and Flex on one page	1–4 MP
FLUX.2 Pro API	Balanced quality and cost for production images, up to 8 references	1–4 MP
FLUX.2 Max API	The highest-quality FLUX.2 output, up to 8 references	1–4 MP
FLUX.2 Flex API	Adjustable steps and guidance for typography and layout-heavy designs	1–4 MP
FLUX.1 Kontext API	Choosing between FLUX.1 Kontext Pro and Max on one page	About 1 MP
FLUX.1 Kontext Pro API	Context-aware edits at a fixed price per image, up to 4 references	About 1 MP
FLUX.1 Kontext Max API	Higher-quality Kontext edits with stronger prompt adherence	About 1 MP

Model

Best for

Output

FLUX 3 Image API

The FLUX 3 API for images: generation and editing with up to 10 references, search grounding and output up to 4K

768sq to 4K (about 16 MP)

FLUX 3 Image Klein API

Lower-cost FLUX 3 images with seed, 1–16 steps and PNG or JPEG output

768sq to 4K (about 16 MP)

FLUX 3 Video API

Text to video, 1–10 keyframes, video continuation and drafts, with synced audio

HD or FHD, 5–20 s

FLUX.2 APIThis page

Choosing between FLUX.2 Pro, Max and Flex on one page

1–4 MP

FLUX.2 Pro API

Balanced quality and cost for production images, up to 8 references

1–4 MP

FLUX.2 Max API

The highest-quality FLUX.2 output, up to 8 references

1–4 MP

FLUX.2 Flex API

Adjustable steps and guidance for typography and layout-heavy designs

1–4 MP

FLUX.1 Kontext API

Choosing between FLUX.1 Kontext Pro and Max on one page

About 1 MP

FLUX.1 Kontext Pro API

Context-aware edits at a fixed price per image, up to 4 references

About 1 MP

FLUX.1 Kontext Max API

Higher-quality Kontext edits with stronger prompt adherence

About 1 MP

FLUX.2 API

FLUX.2 API Pricing