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OpenKey

o3 Pro

OpenAIReleased Jun 10, 2025

The o-series of models are trained with reinforcement learning to think before they answer and perform complex reasoning. The o3-pro model uses more compute to think harder and provide consistently...

Try in playground
Context window
200K tokens
Max output
100K tokens
Input
text, file, image
Output
text
Tokenizer
GPT
Knowledge cutoff
Jun 30, 2024
Released
Jun 10, 2025
Reasoning
optional

Pricing

Per 1M tokens. The provider price and our flat 3% fee are separate columns — what you pay is their sum.

Per 1M tokensProvider+ 3% feeYou pay
Input$20.00$0.600$20.60
Output$80.00$2.40$82.40

Supported parameters

  • include_reasoning
  • max_tokens
  • reasoning
  • response_format
  • seed
  • structured_outputs
  • tool_choice
  • tools

Call it

OpenAI-compatible: point your SDK at api.openkey.ai/v1 and use model openai/o3-pro.

Code sample language
curl https://api.openkey.ai/v1/chat/completions \
  -H "Authorization: Bearer $OPENKEY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "openai/o3-pro",
    "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="openai/o3-pro",
    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: "openai/o3-pro",
  messages: [{ role: "user", content: "Hello" }],
});
console.log(completion.choices[0].message.content);

Questions

How much does o3 Pro cost via API?
Through OpenKey, o3 Pro costs $20.60 per 1M input tokens and $82.40 per 1M output tokens. That is the provider price ($20.00 / $80.00) plus a flat 3% fee — nothing else.
What is o3 Pro's context window?
o3 Pro accepts up to 200K tokens of context and returns up to 100K tokens per request.
Is o3 Pro OpenAI-compatible?
Yes. Send requests to OpenKey's /v1/chat/completions endpoint with model "openai/o3-pro" using any OpenAI SDK — only the base URL and API key change.
What inputs does o3 Pro support?
o3 Pro accepts text, file, image input and produces text output. Its knowledge cutoff is Jun 30, 2024.

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