Overview
Flux 1.1 Ultra is a premium text-to-image model developed by Black Forest Labs, designed to generate high-resolution 4-megapixel visuals in roughly 10 seconds. Building on Flux 1.1 Pro, it delivers sharp, photorealistic results with strict prompt adherence. The model features distinct "Ultra" and "Raw" generation modes, making it highly effective for professional workflows, polished marketing assets, and candid, natural-looking photography.
Specifications · Text to image
- Input mode
- Text to image
- Aspect ratios
- 16:9, 9:16, 1:1, 4:3, 3:4, 21:9, 9:21, 3:2, 2:3
- Resolutions
- fixed
Pricing
Build with this model: the Flux 1.1 Ultra API on the Hedra Developer Platform.
Flux 1.1 Ultra API →Real output · generated with Flux 1.1 Ultra
Best of Flux 1.1 Ultra
Prompting
Prompt tips
- Optimize for Raw Mode: When aiming for lifelike photography, enable Raw mode and use terms like "candid photography," "amateur photo," or "uncropped" to maximize natural aesthetics.
- Drop the Quality Tags: Because of its native high-resolution capabilities, you do not need to pad prompts with "4k, 8k, ultra-detailed, masterpiece." Keep descriptions focused on the actual subject and scene.
- Use Natural Language: The model responds best to conversational, descriptive sentences detailing the subject, lighting, and camera angle, rather than comma-separated keyword lists.
- Specify Composition Explicitly: The model has high prompt adherence, so detailed instructions regarding camera lenses (e.g., "shot on 35mm lens") and lighting (e.g., "dramatic rim lighting") translate directly to the output.
About the model
Questions, answered
What is Flux 1.1 Ultra best used for?
Flux 1.1 Ultra by Black Forest Labs is designed for generating ultra-high-resolution, photorealistic images. It can produce outputs up to 4 megapixels (2048x2048), making it ideal for detailed artwork, large-format prints, and full-width hero images. Community consensus highlights its exceptional prompt adherence, sharp text rendering, and ability to handle complex compositions without losing fine details.
When was Flux 1.1 Ultra released and what is its lineage?
Black Forest Labs announced Flux 1.1 Ultra on November 6, 2024. It serves as a high-resolution upgrade to the standard Flux 1.1 Pro, delivering 4x the resolution while maintaining fast generation speeds. The Flux family lineage later expanded to include the [Flux.2 pro] generation and specialized context-editing models like Flux Kontext Pro.
What is 'Raw Mode' and when should I use it?
Introduced alongside the Ultra update, Raw Mode is a generation setting that produces a more natural, less synthetic aesthetic. It is highly recommended by the community for mimicking authentic, candid photography. Raw mode captures genuine textures and significantly improves realism in nature and human portraits by avoiding the over-stylized 'AI look' common in default outputs.
How should I prompt Flux 1.1 Ultra for the best results?
Because of its 12-billion-parameter architecture, Flux 1.1 Ultra follows complex instructions incredibly well. Use direct, descriptive language and specify exact lighting, camera angles, and textures. If you need text in your image, wrap the exact words in quotes. For more advanced techniques, check out Adobe's Firefly/Flux prompting guide.