Models
fal
FLUX.2 [dev] Flash

fal

llms.txt

FLUX.2 [dev] Flash

AI Image Editing Model

Mode:

All Text to Image Image Edit

Image #6 Text-to-Image

Fast distilled version of Black Forest Labs' FLUX.2 [dev] optimized for speed and cost efficiency.

FLUX.2 [dev] Flash generated image of Cinematic wide shot of a weathered vintage wooden workbench in an artist's su...

FLUX.2 [dev] Flash generated image of A hyper-realistic close-up of an elderly craftsman's weathered hands meticulo...

Try Model

2048 x 2048

Max Resolution

Supported Modes

Text to Image Image Edit

Active

Details

Model ID

flux.2-dev-flash

Creator

fal

Family

flux.2

Released

December 2025

Max Input Images

Ready to integrate?

Access flux.2-dev-flash via our unified API.

Create Account

Available at 1 provider

Starting from

$0.0050 /image via fal.ai

Prices shown are in USD · Some prices estimated from per-megapixel or per-token pricing

Full pricing details

Provider Performance

Fastest generation through fal at 8,093ms median latency with 98.2% success rate.

Aggregated from real API requests over the last 30 days.

Generation Time

fal

p95: 36,022ms

Success Rate

fal

98.2%

55 / 56 requests

Time to First Byte

fal

7,781ms

p95: 32,869ms

Provider Rankings

#	Provider	p50 Gen Time	p95 Gen Time	Success Rate	TTFB (p50)
1	fal	8,093ms	36,022ms	98.2%	7,781ms

Data updated every 15 minutes. Based on all API requests through Lumenfall over the last 30 days.

Providers & Pricing (1)

FLUX.2 [dev] Flash is available exclusively through fal.ai, starting at $0.005/image.

fal.ai

Image Edit

fal/flux.2-dev-flash-edit

Provider Model ID: fal-ai/flux-2/flash/edit

Input

Megapixel

$0.0050

Output

Megapixel

$0.0050

Pricing Notes (4)

• Resolution is rounded up to the next megapixel, separately for each reference image and the generated image
• 1 megapixel = 1024x1024 pixels
• Each reference image is counted separately (minimum 1 MP each)
• Images exceeding 4 megapixels are resized to 4 megapixels

View official pricing • As of Dec 30, 2025

FLUX.2 [dev] Flash API OpenAI-compatible

Integrate FLUX.2 [dev] Flash via Lumenfall’s OpenAI-compatible API to programmatically generate high-resolution images and perform complex image editing. This endpoint provides low-latency access to fast-distilled text-to-image capabilities for real-time media applications.

Base URL

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

Model

flux.2-dev-flash

Code Examples

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.2-dev-flash" \

  -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.2-dev-flash',

  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.2-dev-flash",

    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. Text prompt for image generation	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") 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

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. Up to 4 images per request.	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

Provider-specific passthrough fields, available only when the request is routed to the listed provider.

Parameter	Type	Description	Modes
Universal
`cfg_scale`	number	Classifier-free guidance scale — higher values stick more closely to the prompt	T2I Edit
`prompt_enhancement`	string	Whether an LLM rewrites/expands the prompt before generation (off, on) `off` `on`	T2I Edit
fal
`enable_safety_checker`	boolean	If set to true, the safety checker will be enabled.	T2I Edit
`sync_mode`	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

FLUX.2 [dev] Flash FAQ

How much does FLUX.2 [dev] Flash cost?

FLUX.2 [dev] Flash starts at $0.005 per image through Lumenfall. Pricing varies by provider. Lumenfall does not add any markup to provider pricing.

How do I use FLUX.2 [dev] Flash via API?

You can use FLUX.2 [dev] Flash through Lumenfall's OpenAI-compatible API. Send requests to the unified endpoint with model ID "flux.2-dev-flash". Code examples are available in Python, JavaScript, and cURL.

Which providers offer FLUX.2 [dev] Flash?

FLUX.2 [dev] Flash is available through fal.ai on Lumenfall. Lumenfall automatically routes requests to the best available provider.

What is the maximum resolution for FLUX.2 [dev] Flash?

FLUX.2 [dev] Flash supports images up to 2048x2048 resolution.

Overview

FLUX.2 [dev] Flash is a distilled, high-speed variant of Black Forest Labs’ FLUX.2 [dev] model, developed by fal. It is a text-to-image and image-to-image model architected to provide high-fidelity visual output with significantly lower latency and inference costs than the standard base model. By utilizing distillation techniques, it maintains the structural intelligence of the FLUX.2 architecture while requiring fewer sampling steps to produce a final image.

Strengths

Inference Speed: Significantly reduces generation time compared to the standard FLUX.2 [dev] model, making it suitable for near real-time applications and rapid prototyping.
Text Rendering: Retains the core architectural ability to render complex, legible text within generated images with high accuracy.
Prompt Adherence: Shows strong alignment with complex, multi-layered natural language prompts, following specific instructions regarding composition and object placement.
Cost Efficiency: With a starting price of $0.005, it offers a more economical pathway for developers to run high-volume image generation workloads without a proportional increase in compute spend.

Limitations

Non-Commercial License: Distributed under a non-commercial license, which restricts its use to research, hobbyist projects, and personal experimentation rather than production-grade commercial products.
Fine Detail Compression: As a distilled model, it may exhibit slightly less texture nuance or micro-detail in extremely complex scenes compared to the full-parameter version of FLUX.2 [dev].
Step Sensitivity: While optimized for fewer steps, pushing the model to extremely low step counts (e.g., 1-2 steps) may result in occasional artifacts not present in the standard dev model.

Technical Background

FLUX.2 [dev] Flash belongs to the FLUX.2 family of flow-matching transformer models. It employs a distillation process designed to compress the sampling trajectory, allowing the model to achieve convergence in a fraction of the iterations required by the original teacher model. This approach prioritizes computational efficiency while preserving the underlying latent representation space established by Black Forest Labs.

Best For

This model is ideal for developers building interactive creative tools, rapid ideation workflows, or research projects where low latency is critical. It is particularly effective for generating UI mockups, social media assets, or storyboard frames where fast iteration is more valuable than maximum-parameter rendering. FLUX.2 [dev] Flash is available for testing and integration through Lumenfall’s unified API and interactive playground.

Try FLUX.2 [dev] Flash in Playground

Generate images with custom prompts — no API key needed.

Open Playground