What is FLUX Kontext [max]?

FLUX Kontext [max] is the premium tier of Black Forest Labs' in-context editing model. It takes a source image and a text prompt, then applies targeted edits while preserving subject identity — with the best prompt adherence and typography in the Kontext family.

How much does FLUX Kontext [max] cost on Runflow?

$0.08 per image, flat pricing. Cold starts are not billed.

How does FLUX Kontext [max] compare to FLUX Kontext [pro]?

FLUX Kontext [max] has stronger prompt adherence, better typography, and higher consistency on complex edits. [pro] is faster and cheaper ($0.04/image) for standard editing workflows. Both preserve subject identity across transformations.

What kind of edits can FLUX Kontext do?

Background changes, outfit swaps, style transfers, text overlays, lighting adjustments, scene transforms — all while keeping the subject, product, or character consistent. No masks or regions needed — just describe the edit in natural language.

Can I use FLUX Kontext [max] commercially?

Yes. FLUX Kontext [max] is available under a commercial license for production applications, SaaS products, and client work.

Do I need to manage GPUs or infrastructure?

No. Runflow handles all GPU provisioning, scaling, and failover. You make an API call, you get back an image.

Black Forest Labs

FLUX Kontext [max] API

FLUX Kontext [max] — premium in-context editing with top-tier prompt adherence and typography. $0.08/image, commercial.

flux-pro-kontext-max— paramsFlow Transformer with reference conditioning

Updated March 2026·Early access

Run the API How Sentinel controls quality

Price

$0.08/image

Per image, flat pricing

Cold Start

5–10s

Not billed, handled by Runflow

Quality Score

Coming soon

Sentinel benchmarks in progress

FLUX Kontext model family by Black Forest Labs

In-context image editing and generation — multiple tiers on the same Runflow API.

FLUX Kontext [max]

This model

Premium — best prompt adherence and typography, $0.08/image

FLUX Kontext [pro]

Pro

Standard — fast in-context editing with character consistency, $0.04/image

Benchmarked for your use case

Every model on Runflow is scored per vertical — not generic leaderboard numbers. Scores come from domain-expert evaluation on real production prompts.

Use Case	Assessment	Notes
Portrait	Strong	Premium identity preservation across scene changes
Fashion	Strong	Outfit swaps and style transfers with consistent subject identity
Product	Strong	Context changes while preserving product detail and branding
Creative	Strong	Best-in-class typography and text overlay generation

API Parameters

Full parameter reference for the flux-pro-kontext-max model endpoint.

Parameter	Type	Required	Description
prompt	string	required	Editing instruction describing the desired transformation.
image_url	string	required	URL of the source image to edit.
aspect_ratio	string	optional	Output aspect ratio. Options: square_hd, square, portrait_4_3, portrait_16_9, landscape_4_3, landscape_16_9, 21:9, 9:21, and more.
num_images	integer	optional	Number of images to generate per request. Range: 1–4. Default: 1.
guidance_scale	float	optional	How closely the model follows the prompt. Range: 1–20. Default: 3.5.
output_format	string	optional	Output format. Options: "jpeg", "png". Default: "jpeg".
safety_tolerance	string	optional	Content moderation strictness. 1 = most strict, 6 = most permissive. Default: 2.
enhance_prompt	boolean	optional	Automatically enhance the prompt for better results. Default: false.
seed	integer	optional	Random seed for reproducible outputs.
sync_mode	boolean	optional	Return media as data URI without storing in request history. Default: false.

Technical Specifications

ArchitectureFlow Transformer with reference conditioning

ModeImage-to-image (in-context editing)

Guidance Scale3.5 (default) · 1–20 range

Max Batch Size4 images per request

Output FormatsJPEG · PNG

TypographyImproved text rendering and overlay generation

Multi-image InputAvailable via experimental /multi endpoint

LicenseCommercial

Why run FLUX Kontext [max] on the Runflow API

Flux AI models are available on many platforms. Here's what makes the Runflow image generation API different.

Best-in-class prompt adherence

FLUX Kontext [max] delivers the highest prompt fidelity in the Kontext family — complex multi-step editing instructions are followed more accurately than [pro].

Premium typography generation

Improved text rendering means legible, well-placed text overlays and in-image typography — useful for marketing creatives, signage, and branded content.

Identity-preserving edits

Change backgrounds, outfits, lighting, and scene context while keeping subjects, products, and brand elements perfectly consistent.

Context-aware understanding

The model understands image content — you can describe edits naturally without specifying regions or masks.

Sentinel quality scoring

Every output is scored by Runflow's Sentinel system for both generation quality and reference fidelity.

Explore other models

Same API, different strengths. Switch models with one parameter change.

Black Forest Labs

Frequently asked questions

Resources

API Documentation

Full endpoint reference, authentication, and response formats.

Sentinel Quality Evaluation

Automated quality gates for every image in your pipeline.

Start generating images with FLUX Kontext [max]

Get API access in minutes. No GPU setup, no infrastructure to manage. Pair with Sentinel to control the quality of every AI-generated image you ship.

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