Gemini 3.1 Pro Preview
GoogleReleased Feb 19, 2026
Gemini 3.1 Pro Preview is Google’s frontier reasoning model, delivering enhanced software engineering performance, improved agentic reliability, and more efficient token usage across complex workflows. Building on the multimodal foundation...
- Context window
- 1.0M tokens
- Max output
- 66K tokens
- Input
- audio, file, image, text, video
- Output
- text
- Tokenizer
- Gemini
- Released
- Feb 19, 2026
- Reasoning
- always on
Pricing
Per 1M tokens. The provider price and our flat 3% fee are separate columns — what you pay is their sum.
| Per 1M tokens | Provider | + 3% fee | You pay |
|---|---|---|---|
| Input | $2.00 | $0.060 | $2.06 |
| Output | $12.00 | $0.360 | $12.36 |
| Cache read | $0.200 | $0.0060 | $0.206 |
| Cache write | $0.375 | $0.011 | $0.386 |
Benchmarks
Artificial Analysis
- Intelligence index
- 46.5
- Coding index
- 68.8
- Agentic index
- 21.4
Design Arena
| Category | Elo | Win rate | Rank |
|---|---|---|---|
| agenticgamedevagents | 1149 | 43.8% | #8 |
| agentichtmlslidesagents | 1226 | 55.8% | #5 |
| agenticslidesagents | 1112 | 33.8% | #8 |
| agenticslides(html)agents | 1219 | 54.4% | #5 |
| agenticslides(python-pptx)agents | 1107 | 33.9% | #8 |
| androidnativeagents | 1059 | 39.2% | #25 |
| Full-stackagents | 1139 | 45% | #16 |
| godotgamedevagents | 1220 | 53.6% | #6 |
| htmlslidesagents | 1209 | 52.9% | #6 |
| Mobile appsagents | 1176 | 46.6% | #22 |
| pptxslidesagents | 1110 | 34.1% | #8 |
| python-pptxslidesagents | 1109 | 31.9% | #9 |
| Web appsagents | 1196 | 48.2% | #13 |
| 3Dmodels | 1303 | 61.4% | #17 |
| ASCII artmodels | 1314 | 63.4% | #4 |
| Codemodels | 1290 | 64.2% | #18 |
| Data vizmodels | 1270 | 60.6% | #20 |
| Game devmodels | 1264 | 54.6% | #26 |
| SVGmodels | 1347 | 70.3% | #2 |
| UI componentsmodels | 1322 | 68.1% | #8 |
| Websitesmodels | 1294 | 64.3% | #15 |
Head-to-head preference voting. How we filter and rank
Supported parameters
- include_reasoning
- max_tokens
- reasoning
- response_format
- seed
- stop
- structured_outputs
- temperature
- tool_choice
- tools
- top_p
Call it
OpenAI-compatible: point your SDK at api.openkey.ai/v1 and use model google/gemini-3.1-pro-preview.
curl https://api.openkey.ai/v1/chat/completions \
-H "Authorization: Bearer $OPENKEY_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "google/gemini-3.1-pro-preview",
"messages": [{"role": "user", "content": "Hello"}]
}'import os
from openai import OpenAI
client = OpenAI(
base_url="https://api.openkey.ai/v1",
api_key=os.environ["OPENKEY_API_KEY"],
)
completion = client.chat.completions.create(
model="google/gemini-3.1-pro-preview",
messages=[{"role": "user", "content": "Hello"}],
)
print(completion.choices[0].message.content)import OpenAI from "openai";
const client = new OpenAI({
baseURL: "https://api.openkey.ai/v1",
apiKey: process.env.OPENKEY_API_KEY,
});
const completion = await client.chat.completions.create({
model: "google/gemini-3.1-pro-preview",
messages: [{ role: "user", content: "Hello" }],
});
console.log(completion.choices[0].message.content);Questions
- How much does Gemini 3.1 Pro Preview cost via API?
- Through OpenKey, Gemini 3.1 Pro Preview costs $2.06 per 1M input tokens and $12.36 per 1M output tokens. That is the provider price ($2.00 / $12.00) plus a flat 3% fee — nothing else.
- What is Gemini 3.1 Pro Preview's context window?
- Gemini 3.1 Pro Preview accepts up to 1.0M tokens of context and returns up to 66K tokens per request.
- Is Gemini 3.1 Pro Preview OpenAI-compatible?
- Yes. Send requests to OpenKey's /v1/chat/completions endpoint with model "google/gemini-3.1-pro-preview" using any OpenAI SDK — only the base URL and API key change.
- What inputs does Gemini 3.1 Pro Preview support?
- Gemini 3.1 Pro Preview accepts audio, file, image, text, video input and produces text output.
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