OpenLuxGemini 3 Pro Image Preview vs Gemini 3.1 Flash Image Preview
Gemini 3 Pro Image Preview and Gemini 3.1 Flash Image Preview both run on OpenLux behind one OpenAI-compatible endpoint. Gemini 3 Pro Image Preview is metered at $0.0243 per request (-91% vs official rates); Gemini 3.1 Flash Image Preview at $0.0122 per request (-92% vs official rates). Gemini 3.1 Flash Image Preview is the lower-cost option per unit — about 50% cheaper on the same OpenLux endpoint. This page compares their rates, strengths and best-fit workloads so you can route each request to the right model.
The short version
In practice the two models are complements, not substitutes: Gemini 3 Pro Image Preview suits workloads that need image generation and creative pipelines. Gemini 3.1 Flash Image Preview is the better fit when you need image generation and creative pipelines. Both are called with the same OpenLux key, so switching between them is a one-field change to the model name.
Choose Gemini 3 Pro Image Preview when
- You need image generation and creative pipelines.
Choose Gemini 3.1 Flash Image Preview when
- You need image generation and creative pipelines.
- Unit cost is the deciding factor for this workload.
Rates on OpenLux
| Model | Provider | Rate | Discount |
|---|---|---|---|
| Gemini 3 Pro Image Preview | $0.0243 per request | -91% | |
| Gemini 3.1 Flash Image Preview | $0.0122 per request | -92% |
Rates follow official provider pricing and are billed in USD. See the full catalogue and pricing plans for credit allowances.
One snippet, two models
Gemini 3 Pro Image Preview and Gemini 3.1 Flash Image Preview share the same OpenAI-compatible request shape. Run the same code against both and compare the answers on your own workload.
from openai import OpenAI
client = OpenAI(
api_key="sk-openlux-...",
base_url="https://openlux.lol/v1",
)
for model in ["gemini-3-pro-image-preview", "gemini-3.1-flash-image-preview"]:
resp = client.chat.completions.create(
model=model,
messages=[{"role": "user", "content": "Summarise this release note for me."}],
)
print(model, "->", resp.choices[0].message.content)Any OpenAI SDK works the same way — see the docs for streaming, tools and error codes.
Gemini 3 Pro Image Preview vs Gemini 3.1 Flash Image Preview questions
How much do Gemini 3 Pro Image Preview and Gemini 3.1 Flash Image Preview cost on OpenLux?
Gemini 3 Pro Image Preview is metered pay as you go at $0.0243 per request, a -91% discount on official list pricing. Gemini 3.1 Flash Image Preview is metered at $0.0122 per request, a -92% discount. There is no subscription requirement: usage is billed in USD and every request is visible in the console.
Can I call Gemini 3 Pro Image Preview and Gemini 3.1 Flash Image Preview with the same API key?
Yes. Both models sit behind the same OpenAI-compatible endpoint at https://openlux.lol/v1. Keep the same key and change only the "model" field to switch between gemini-3-pro-image-preview and gemini-3.1-flash-image-preview — request and response shapes stay identical.
Which is cheaper, Gemini 3 Pro Image Preview or Gemini 3.1 Flash Image Preview?
Gemini 3.1 Flash Image Preview costs less per unit: $0.0122 per request versus $0.0243 per request, about 50% lower for the same volume. Over a month of production traffic the difference compounds, and the console shows cost per request in real time.
When should I pick Gemini 3 Pro Image Preview over Gemini 3.1 Flash Image Preview?
In practice the two models are complements, not substitutes: Gemini 3 Pro Image Preview suits workloads that need image generation and creative pipelines. Gemini 3.1 Flash Image Preview is the better fit when you need image generation and creative pipelines. Both are called with the same OpenLux key, so switching between them is a one-field change to the model name.
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Route every request to the right model
OpenLux keeps Gemini 3 Pro Image Preview, Gemini 3.1 Flash Image Preview and every other model behind one key, one endpoint and one bill. Start with free trial credit and switch models without touching your code.