FLUX.1 Krea [dev]

Name: FLUX.1 Krea [dev]
Brand: Black Forest Labs
Price: 0.025 USD
Availability: InStock

AI Image Generation Model

Image

Black Forest Labs' aesthetically-tuned 12-billion parameter flow transformer optimized for high-quality images with incredible aesthetics, suitable for personal and commercial use

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2048 x 2048

Max Resolution

Supported Modes

Text to Image Image Edit

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Details

Model ID

flux.1-krea-dev

Creator

Black Forest Labs

Family

flux.1

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Access flux.1-krea-dev via our unified API.

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Available at 2 providers

Starting from

$0.025 /image via fal.ai, Replicate

Prices shown are in USD

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Providers & Pricing (3)

FLUX.1 Krea [dev] is available from 3 providers, with per-image pricing starting at $0.025 through fal.ai.

fal.ai

Text to Image

fal/flux.1-krea-dev

Provider Model ID: fal-ai/flux/krea

$0.025 /image

View pricing details

fal.ai

Image Edit

fal/flux.1-krea-dev-edit

Provider Model ID: fal-ai/flux/krea/image-to-image

$0.025 /image

View pricing details

Replicate

Text to Image Image Edit

replicate/flux.1-krea-dev

Provider Model ID: black-forest-labs/flux-krea-dev

$0.025 /image

View pricing details

FLUX.1 Krea [dev] API OpenAI-compatible

Integrate FLUX.1 Krea [dev] via the Lumenfall OpenAI-compatible API to generate high-fidelity, aesthetically-tuned images using Black Forest Labs' advanced text-to-image technology.

Base URL

https://api.lumenfall.ai/openai/v1

Model

flux.1-krea-dev

Code Examples

Text to Image

/v1/images/generations

curl -X POST \

  https://api.lumenfall.ai/openai/v1/images/generations \

  -H "Authorization: Bearer $LUMENFALL_API_KEY" \

  -H "Content-Type: application/json" \

  -d '{

    "model": "flux.1-krea-dev",

    "prompt": "",

    "size": "1024x1024"

}'

# Response:

# { "created": 1234567890, "data": [{ "url": "https://...", "revised_prompt": "..." }] }

import OpenAI from 'openai';

const client = new OpenAI({

  apiKey: 'YOUR_API_KEY',

  baseURL: 'https://api.lumenfall.ai/openai/v1'

});

const response = await client.images.generate({

  model: 'flux.1-krea-dev',

  prompt: '',

  size: '1024x1024'

});

// { created: 1234567890, data: [{ url: "https://...", revised_prompt: "..." }] }

console.log(response.data[0].url);

from openai import OpenAI

client = OpenAI(

    api_key="YOUR_API_KEY",

    base_url="https://api.lumenfall.ai/openai/v1"

response = client.images.generate(

    model="flux.1-krea-dev",

    prompt="",

    size="1024x1024"

# { created: 1234567890, data: [{ url: "https://...", revised_prompt: "..." }] }

print(response.data[0].url)

Image Edit

/v1/images/edits

curl -X POST \

  https://api.lumenfall.ai/openai/v1/images/edits \

  -H "Authorization: Bearer $LUMENFALL_API_KEY" \

  -F "model=flux.1-krea-dev" \

  -F "[email protected]" \

  -F "prompt=Add a starry night sky to this image" \

  -F "size=1024x1024"

# Response:

# { "created": 1234567890, "data": [{ "url": "https://...", "revised_prompt": "..." }] }

import OpenAI from 'openai';

import fs from 'fs';

const client = new OpenAI({

  apiKey: 'YOUR_API_KEY',

  baseURL: 'https://api.lumenfall.ai/openai/v1'

});

const response = await client.images.edit({

  model: 'flux.1-krea-dev',

  image: fs.createReadStream('source.png'),

  prompt: 'Add a starry night sky to this image',

  size: '1024x1024'

});

// { created: 1234567890, data: [{ url: "https://...", revised_prompt: "..." }] }

console.log(response.data[0].url);

from openai import OpenAI

client = OpenAI(

    api_key="YOUR_API_KEY",

    base_url="https://api.lumenfall.ai/openai/v1"

response = client.images.edit(

    model="flux.1-krea-dev",

    image=open("source.png", "rb"),

    prompt="Add a starry night sky to this image",

    size="1024x1024"

# { created: 1234567890, data: [{ url: "https://...", revised_prompt: "..." }] }

print(response.data[0].url)

Parameter Reference

Required Supported Not available

Core Parameters

Parameter	Type	Description	Modes
`prompt`	string	Required. Edit instruction for the image	T2I Edit
`seed`	integer	Random seed for reproducibility	T2I Edit

Size & Layout

Parameter	Type	Description	Modes
`size`	string	Image dimensions as WxH pixels (e.g. "1024x1024") or aspect ratio (e.g. "16:9") WxH determines both shape and scale (aspect_ratio and resolution are ignored when size is provided). W:H format is equivalent to aspect_ratio.	T2I Edit
`aspect_ratio`	string	Aspect ratio of the output image (e.g. "16:9", "1:1") Controls shape independently of scale. Use with resolution to control both. If size is also provided, size takes precedence. Any ratio is accepted and mapped to the nearest supported value.	T2I Edit
`resolution`	string	Output resolution tier (e.g. "1K", "4K") `1K` Controls scale independently of shape. Higher tiers produce larger images and cost more. If size is also provided, size takes precedence for scale. Any tier is accepted and mapped to the nearest supported value.	T2I Edit

Output	`size`		`aspect_ratio` + `resolution`
Flexible
Custom 1–14142px per side	`"WxH"`	—	Any pixel dimensions within model constraints

1K 11 sizes

Output	`size`		`aspect_ratio` + `resolution`
1183 × 887	`"1183x887"`	or	`"4:3"` + `"1K"`
916 × 1145	`"916x1145"`	or	`"4:5"` + `"1K"`
1145 × 916	`"1145x916"`	or	`"5:4"` + `"1K"`
1024 × 1024	`"1024x1024"`	or	`"1:1"` + `"1K"`
887 × 1182	`"887x1182"`	or	`"3:4"` + `"1K"`
836 × 1254	`"836x1254"`	or	`"2:3"` + `"1K"`
1254 × 836	`"1254x836"`	or	`"3:2"` + `"1K"`
768 × 1365	`"768x1365"`	or	`"9:16"` + `"1K"`
1365 × 768	`"1365x768"`	or	`"16:9"` + `"1K"`
670 × 1564	`"670x1564"`	or	`"9:21"` + `"1K"`
1563 × 670	`"1563x670"`	or	`"21:9"` + `"1K"`

How these parameters work

size

Exact pixel dimensions

"1920x1080"

aspect_ratio

Shape only, default scale

"16:9"

resolution

Scale tier, preserves shape

"1K"

Priority when combined

size › aspect_ratio + resolution › aspect_ratio › resolution

size is most specific and always wins. aspect_ratio and resolution control shape and scale independently.

How matching works

Shape matching – we pick the closest supported ratio. Ask for 7:1 on a model with 4:1 and 8:1, you get 8:1.

Scale matching – providers use different tier formats: K tiers (0.5K 1K 2K 4K) or megapixel tiers (0.25 1). If the exact tier isn't available, you get the nearest one.

Dimension clamping – if a model has pixel limits, we clamp dimensions to fit and keep the aspect ratio intact.

Media Inputs

Parameter	Type	Description	Modes
`image`	file	Required. Input image(s) to edit Supports PNG, JPEG, WebP.	T2I Edit

Output & Format

Parameter	Type	Description	Modes
`response_format`	string	How to return the image `url` `b64_json` Default: `"url"`	T2I Edit
`output_format`	string	Output image format `png` `jpeg` `gif` `webp` `avif` Gateway converts to requested format if provider doesn't support it natively.	T2I Edit
`output_compression`	integer	Compression level for lossy formats (JPEG, WebP, AVIF)	T2I Edit
`n`	integer	Number of images to generate Default: `1` Gateway generates multiple images in parallel even if provider only supports 1.	T2I Edit

Additional Parameters

Parameter	Type	Description	Modes
`cfg_scale`	number	Classifier-free guidance scale — higher values stick more closely to the prompt	T2I Edit
`strength`	number	How much to transform the input image: 0 keeps it unchanged, 1 fully regenerates from the prompt	T2I Edit
`acceleration` fal	string	The speed of the generation. The higher the speed, the faster the generation. `high` `none` `regular`	T2I Edit
`disable_safety_checker` replicate	boolean	Disable safety checker for generated images.	T2I Edit
`enable_safety_checker` fal	boolean	If set to true, the safety checker will be enabled.	T2I Edit
`go_fast` replicate	boolean	Run faster predictions with model optimized for speed (currently fp8 quantized); disable to run in original bf16. Note that outputs will not be deterministic when this is enabled, even if you set a seed.	T2I Edit
`megapixels` replicate	string	Approximate number of megapixels for generated image `0.25` `1`	T2I Edit
`num_inference_steps`	integer	The number of inference steps to perform.	T2I Edit
`output_quality` replicate	integer	Quality when saving the output images, from 0 to 100. 100 is best quality, 0 is lowest quality. Not relevant for .png outputs	T2I Edit
`sync_mode` fal	boolean	If `True`, the media will be returned as a data URI and the output data won't be available in the request history.	T2I Edit

Parameter Normalization

How we handle parameters across different providers

Not every provider speaks the same language. When you send a parameter, we handle it in one of four ways depending on what the model supports:

Behavior	What happens	Example
`passthrough`	Sent as-is to the provider	style, quality
`renamed`	Same value, mapped to the field name the provider expects	prompt
`converted`	Transformed to the provider's native format	size
`emulated`	Works even if the provider has no concept of it	n, response_format

Parameters we don't recognize pass straight through to the upstream API, so provider-specific options still work.

Full API Reference Authentication, endpoints, and more

Gallery

View all 2 images

FLUX.1 Krea [dev] FAQ

How much does FLUX.1 Krea [dev] cost?

FLUX.1 Krea [dev] starts at $0.025 per image through Lumenfall. Pricing varies by provider. Lumenfall does not add any markup to provider pricing.

How do I use FLUX.1 Krea [dev] via API?

You can use FLUX.1 Krea [dev] through Lumenfall's OpenAI-compatible API. Send requests to the unified endpoint with model ID "flux.1-krea-dev". Code examples are available in Python, JavaScript, and cURL.

Which providers offer FLUX.1 Krea [dev]?

FLUX.1 Krea [dev] is available through fal.ai and Replicate on Lumenfall. Lumenfall automatically routes requests to the best available provider.

What is the maximum resolution for FLUX.1 Krea [dev]?

FLUX.1 Krea [dev] supports images up to 2048x2048 resolution.

Overview

FLUX.1 Krea [dev] is a 12-billion parameter text-to-image model developed by Black Forest Labs, specifically fine-tuned for enhanced visual appeal and artistic composition. As a specialized variant of the FLUX.1 [dev] model, it utilizes a flow transformer architecture to generate high-fidelity images that prioritize stylized, “pro-photographic” aesthetics. It balances technical precision with a tuned aesthetic bias, making it suitable for high-end creative projects and commercial prototyping.

Strengths

High Aesthetic Quality: The model is specifically tuned to produce images with superior lighting, composition, and color grading compared to the base FLUX.1 [dev] model.
Complex Prompt Adherence: Inherit to the FLUX.1 architecture, this model excels at following multifaceted instructions, including spatial relationships and specific stylistic modifiers.
Text Rendering Accuracy: It maintains the family’s ability to render legible, accurate typography and intricate details within the image canvas.
Artistic Versatility: While it excels at realism, it also demonstrates a heightened capacity for stylized outputs, such as digital art and cinematic concept work.

Limitations

Resource Intensive: At 12 billion parameters, it requires significant computational power for inference, resulting in higher latency compared to “schnell” or smaller distilled models.
Aesthetic Bias: The fine-tuning that gives the model its artistic edge may sometimes result in a “processed” or overly stylized look, which might not be ideal for users seeking raw, unedited documentary-style photography.
Not a Foundation Model: Because it is a derivative of the [dev] model, it may carry similar license restrictions regarding massive-scale commercial redistribution compared to the “pro” versions.

Technical Background

FLUX.1 Krea [dev] is based on a flow-based transformer architecture, a design choice that improves upon traditional diffusion methods by directly modeling the probability flow. This approach allows for more efficient sampling and better handling of high-resolution details. The “Krea” variant involves a post-training fine-tuning phase focused on a curated dataset of high-aesthetic images, refining the model’s weights to favor visually pleasing compositions without sacrificing the base model’s structural intelligence.

Best For

This model thrives in professional creative workflows where visual “pop” is as important as prompt accuracy, such as creating social media assets, marketing collateral, and high-fidelity concept art. It is particularly effective for users who want “production-ready” images that require minimal post-processing or color grading.

FLUX.1 Krea [dev] is available through Lumenfall’s unified API and playground, allowing developers to integrate these high-aesthetic capabilities into their applications with zero infrastructure overhead.

Try FLUX.1 Krea [dev] in Playground

Generate images with custom prompts — no API key needed.

Open Playground