o3 — OpenAI | Modeldex

o3

Active83.5Frontier

OpenAI's most powerful reasoning model, successor to o1.

Updated 4 days agoStructured data from Modeldex catalog

VisionMathAgenticLong contextFrontierReasoning

Knowledge cutoff

Jun 30, 2024(1.8 years ago)

API release

Apr 16, 2025(1.0 years ago)

Intelligence Index

83.5/ 100

Frontierweighted across 7 benchmarks

Math: 97.3
Reasoning: 87.7
General knowledge: 86.1
Coding: 62.8

Computed as the mean of per-category averages across MMLU, GPQA, SWE-bench, HumanEval, MATH, GSM8K, AIME, Aider Polyglot and more. See each benchmark for methodology.

Overview

o3 is OpenAI's top-tier reasoning model trained with reinforcement learning on chain-of-thought. It leads on AIME, GPQA, and SWE-bench across all published models as of mid-2025.

History

o3 became available via the OpenAI API on 2025-04-16.

Training & availability

Training data has a knowledge cutoff of 2024-06-30 — information about events after that date is unlikely to appear in the model's responses. OpenAI has not released the underlying model weights — access is via their hosted API only.

Capabilities

Context window: 200K tokens.
Max output: 100K tokens.
Input modalities: text, image.
Intelligence Index: 83.5/100.

Strongest categories: Math (97), Reasoning (88), General knowledge (86).

Recommended for: vision, math, agentic, long-context, frontier, reasoning.

Limitations

The knowledge cutoff is 21 months old — this model will not know about recent events, releases, or API changes.

Pricing

Input: $2.0000 per 1M tokens
Output: $8.0000 per 1M tokens

Use the cost calculator above to estimate monthly spend for your workload.

Quick start

Minimal example using the openai API. Copy, paste, replace the key.

from openai import OpenAI

client = OpenAI(api_key="sk-...")
resp = client.chat.completions.create(
    model="o3",
    messages=[{"role": "user", "content": "Explain quantum computing in one sentence."}],
)
print(resp.choices[0].message.content)

Cost calculator

Estimate your monthly bill. Presets are typical workload sizes.

Input tokens / month5.0M

@ $2/1M

Output tokens / month2.0M

@ $8/1M

Input cost

$10

5.0M × $2/1M

Output cost

$16

2.0M × $8/1M

Total / month

$26

$312 / year

Benchmarks

Benchmark	Score	Source
AIME 2024Math	96.7% accuracy	Self-reported OpenAI o3 system card
Aider PolyglotCoding	53.8% pass@2	Third-party Papers With Code
GPQA DiamondReasoning	87.7% accuracy	Self-reported OpenAI o3 system card

Integrations & tooling support

Tool calling: Supported
Structured outputs: Supported

Price vs quality

Great value

Strong performance at mid-tier pricing.

Quality percentile: 89.9%
Effective price: $6.5/1M
Pricing breakdown: $2/1M in
$8/1M out

Community ratings

No ratings yet. Be the first to rate o3.

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