FLUX 1.1 Pro Ultra
FLUX 1.1 Pro Ultra costs $0.072/image on FairStack — a text to image model for Legacy FLUX 1.x workflows, High-resolution needs, Style-controlled generation. No subscription required. Pay per generation with full REST API access. FairStack applies a transparent 20% margin on infrastructure cost so you always see the real price.
What is FLUX 1.1 Pro Ultra?
FLUX 1.1 Pro Ultra is the premium tier of Black Forest Labs' previous-generation FLUX architecture, delivering high-resolution output with strong style control. While superseded by the FLUX 2 family which offers better quality at lower prices, FLUX 1.1 Pro Ultra remains a proven model for workflows already built around the FLUX 1.x ecosystem. The model produces high-resolution images with refined detail and reliable style control, benefiting from extensive optimization during its time as the flagship FLUX model. Its output characteristics are well-documented and predictable, which matters for production workflows where consistency is critical. Compared to FLUX 2 Pro at $0.025 which ranks Elo #3 globally and offers better quality at lower cost, FLUX 1.1 Pro Ultra at $0.06 is primarily relevant for backward compatibility. Against Imagen 4 Ultra at $0.06 which delivers superior photorealism, FLUX 1.1 Ultra offers more style versatility. New projects should generally start with FLUX 2 Pro unless specific 1.x behavior is required. Best suited for legacy FLUX 1.x workflows, production pipelines requiring specific 1.1 Ultra output characteristics, and high-resolution generation where migration to FLUX 2 has not yet occurred. Available on FairStack at infrastructure cost plus a 20% platform fee.
Key Features
What are FLUX 1.1 Pro Ultra's strengths?
What are FLUX 1.1 Pro Ultra's limitations?
What is FLUX 1.1 Pro Ultra best for?
How much does FLUX 1.1 Pro Ultra cost?
How does FLUX 1.1 Pro Ultra perform across capabilities?
Ultra quality Flux 1.1 — highest fidelity in the Flux family
How do I use the FLUX 1.1 Pro Ultra API?
curl -X POST https://api.fairstack.ai/v1/generations/image \
-H "Authorization: Bearer $FAIRSTACK_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "flux-pro-1.1-ultra",
"prompt": "Your prompt here"
}'import requests
response = requests.post(
"https://api.fairstack.ai/v1/generations/image",
headers={
"Authorization": f"Bearer {FAIRSTACK_API_KEY}",
"Content-Type": "application/json",
},
json={
"model": "flux-pro-1.1-ultra",
"prompt": "Your prompt here",
},
)
result = response.json()
print(result["url"])const response = await fetch(
"https://api.fairstack.ai/v1/generations/image",
{
method: "POST",
headers: {
Authorization: `Bearer ${process.env.FAIRSTACK_API_KEY}`,
"Content-Type": "application/json",
},
body: JSON.stringify({
model: "flux-pro-1.1-ultra",
prompt: "Your prompt here",
}),
}
);
const result = await response.json();
console.log(result.url);What parameters does FLUX 1.1 Pro Ultra support?
Frequently Asked Questions
How much does FLUX 1.1 Pro Ultra cost?
FLUX 1.1 Pro Ultra costs $0.072/image on FairStack as of 2026-05-13. This price includes FairStack's transparent 20% margin on infrastructure cost. No subscription or monthly fee — you pay per generation only. Minimum deposit is $1.
What is FLUX 1.1 Pro Ultra and what is it best for?
FLUX 1.1 Pro Ultra is the premium tier of Black Forest Labs' previous-generation FLUX architecture, delivering high-resolution output with strong style control. While superseded by the FLUX 2 family which offers better quality at lower prices, FLUX 1.1 Pro Ultra remains a proven model for workflows already built around the FLUX 1.x ecosystem. The model produces high-resolution images with refined detail and reliable style control, benefiting from extensive optimization during its time as the flagship FLUX model. Its output characteristics are well-documented and predictable, which matters for production workflows where consistency is critical. Compared to FLUX 2 Pro at $0.025 which ranks Elo #3 globally and offers better quality at lower cost, FLUX 1.1 Pro Ultra at $0.06 is primarily relevant for backward compatibility. Against Imagen 4 Ultra at $0.06 which delivers superior photorealism, FLUX 1.1 Ultra offers more style versatility. New projects should generally start with FLUX 2 Pro unless specific 1.x behavior is required. Best suited for legacy FLUX 1.x workflows, production pipelines requiring specific 1.1 Ultra output characteristics, and high-resolution generation where migration to FLUX 2 has not yet occurred. Available on FairStack at infrastructure cost plus a 20% platform fee. FLUX 1.1 Pro Ultra is best for Legacy FLUX 1.x workflows, High-resolution needs, Style-controlled generation. Available via FairStack's REST API with curl, Python, and Node.js SDKs.
Does FLUX 1.1 Pro Ultra have an API?
Yes. FLUX 1.1 Pro Ultra is available via FairStack's REST API at api.fairstack.ai. Send a POST request to /v1/generations/image with your API key and prompt. Works with curl, Python requests, Node.js fetch, and any HTTP client. No SDK installation required.
How does FLUX 1.1 Pro Ultra compare to other image models?
FLUX 1.1 Pro Ultra excels at Legacy FLUX 1.x workflows, High-resolution needs, Style-controlled generation. It is a text to image model priced at $0.072/image on FairStack. Key strengths: High resolution output, Proven FLUX architecture. Compare all image models at fairstack.ai/models.
What makes FLUX 1.1 Pro Ultra stand out from other image generators?
FLUX 1.1 Pro Ultra stands out with high resolution output and proven flux architecture. Generation typically takes 15-60 seconds due to its higher-quality processing.
What are the known limitations of FLUX 1.1 Pro Ultra?
Key limitations include: superseded by flux 2 family; higher cost than flux 2 pro ($0.06); older architecture. FairStack documents these transparently so you can choose the right model for your workflow.
How fast is FLUX 1.1 Pro Ultra?
FLUX 1.1 Pro Ultra typically takes 15-60 seconds due to its higher-quality processing. The longer processing time reflects its advanced architecture, which produces higher-quality results than faster alternatives.
What features does FLUX 1.1 Pro Ultra support?
FLUX 1.1 Pro Ultra offers: high resolution output; strong style control; flux 1.1 architecture (proven); premium quality tier. All capabilities are accessible through both the FairStack web interface and REST API.
See how FLUX 1.1 Pro Ultra compares
Side-by-side pricing comparisons with competitors