FLUX.1 Kontext [dev]

FLUX.1 Kontext [dev] is a 12 billion parameter rectified flow transformer from Black Forest Labs, built for in-context image editing. Unlike text-to-image models that generate from a prompt alone, Kontext takes an existing image together with a natural-language edit instruction and produces a revised image that preserves the parts you did not ask to change. It is the open-weight member of the FLUX.1 Kontext family, released to support third-party research and development.

Overview

Kontext performs instruction-based editing: you provide a source image and describe the change you want in plain language, such as adding an object, altering a style, or adjusting a scene. The model applies the edit while maintaining consistency with the original, making it well suited to iterative workflows where an image is refined over several successive edits. It is trained using guidance distillation for more efficient inference.

Key Features

• Change existing images based on a written edit instruction.
• Preserve character, style, and object references across edits without any finetuning.
• Robust consistency that allows an image to be refined through multiple successive edits with minimal visual drift.
• Guidance-distilled training for more efficient generation.
• Open weights intended to drive new scientific research and to empower artists to develop innovative workflows.

Use Cases

• Targeted photo edits driven by a text instruction, for example adding, removing, or modifying elements of a scene.
• Style and appearance changes that keep the subject and composition intact.
• Reference-guided editing that carries a character, style, or object across generations.
• Multi-step creative pipelines where an image is progressively refined edit by edit.

Architecture

FLUX.1 Kontext [dev] is a rectified flow transformer operating in latent space, applying flow matching for in-context image generation and editing. The 12B-parameter transformer is paired with text encoders and a VAE, and conditions generation jointly on the input image and the edit instruction so that outputs remain faithful to the source. A reference implementation and sampling code are provided by Black Forest Labs, and the model is available for both ComfyUI and Diffusers workflows.

Responsible Use

The model repository includes filters for illegal or infringing content, and the FLUX.1 Kontext models were subjected to multiple rounds of pre-release and third-party safety evaluation. In its evaluations, FLUX.1 Kontext [dev] demonstrated high resilience against violative inputs relative to other similar open-weight models. Deployers are expected to keep content filters or manual review in place when using the model.

For full model details, weights, and documentation, see the model card on Hugging Face.