OpenAI o3 API

openai/o3-2025-04-16
OpenAI o3 is a reasoning-focused language model that delivers precise, context-aware answers.
Context
200K tokens
Input
$2.6 / 1M tokens
Output
$10.4 / 1M tokens
Released
Apr 16, 2025

How to use OpenAI o3 API

Install any OpenAI-compatible SDK, point it at api.aimlapi.com/v1, and set the model to openai/o3-2025-04-16.
import requests

r = requests.post(
    "https://api.aimlapi.com/v1/chat/completions",
    headers={"Authorization": "Bearer " + AIMLAPI_KEY},
    json={
      "model": "openai/o3-2025-04-16",
      "messages": [
        {
          "role": "user",
          "content": "Hello!"
        }
      ]
    },
)
print(r.json())
const r = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "openai/o3-2025-04-16",
    "messages": [
      {
        "role": "user",
        "content": "Hello!"
      }
    ]
  }),
});
console.log(await r.json());
curl -X POST https://api.aimlapi.com/v1/chat/completions \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"openai/o3-2025-04-16","messages":[{"role":"user","content":"Hello!"}]}'

OpenAI-compatible — swap the base URL and it works with your existing SDK.

OpenAI o3 API Pricing

TypePrice
Input
$2.6 / 1M tokens
Output
$10.4 / 1M tokens
Cached input
$0.65 / 1M tokens

OpenAI o3 Benchmarks

BenchmarkScoreWhat it measuresSourceRetrieved
SWE-bench Verified
69.1%
Resolving verified real GitHub issuesSourceJuly 8, 2026
GPQA Diamond
83.3%
Google-proof graduate science questions (hardest subset)SourceJuly 8, 2026
AIME 2025
88.9%
Competition mathematics (AIME), 2025SourceJuly 8, 2026
Intelligence
20.2
Composite score across standardised reasoning, knowledge and problem-solving evaluations, measured independently by Artificial AnalysisSourceSeptember 22, 2026
Math
88.3
Composite score across standardised mathematics evaluations, measured independently by Artificial AnalysisSourceSeptember 22, 2026

OpenAI o3 vs other models

ModelInputOutputContextBest for
OpenAI o3
This page
$2.6 / 1M tokens
$10.4 / 1M tokens
200K tokens
Reasoning + agents
$6.5 / 1M tokens
$39 / 1M tokens
1M tokens
Reasoning + agents
$2.6 / 1M tokens
$13 / 1M tokens
1M tokens
Balanced coding + agents
$3.9 / 1M tokens
$19.5 / 1M tokens
1M tokens
Long-context, multimodal & agentic workflows
$1.95 / 1M tokens
$11.7 / 1M tokens
1M tokens
Reasoning + agents

Frequently asked questions

OpenAI o3 has a 200,000 tokens context window and can return up to 100,000 tokens.

OpenAI o3 takes image, text as input and returns text.

Use openai/o3-2025-04-16 as the model id. Requests go to https://api.aimlapi.com/v1/chat/completions.

OpenAI o3 is priced at input $2.6 / 1M tokens, output $10.4 / 1M tokens, cached input $0.65 / 1M tokens.

Yes, OpenAI o3 can stream responses as they are generated.

Yes, OpenAI o3 accepts image input alongside text.

OpenAI o3 was built by OpenAI.

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