Model Tracker

o3

o3 is an AI model made by OpenAI. OpenAI released it on 16 April 2025. It is deprecated. It takes text, image and returns text.

OpenAI

o3 is an AI model made by OpenAI. OpenAI released it on 16 April 2025. It is deprecated. It takes text, image and returns text. Its context window is 200,000 tokens. Its longest answer is 100,000 tokens. Through the API it costs $2.00 per 1M tokens for input and $8.00 per 1M tokens for output. Its knowledge cutoff is 1 June 2024.

Released: 16 April 2025 — openai.com, read 16 October 2026
Status: Deprecated — developers.openai.com, read 16 October 2026
Takes: Text, Image — developers.openai.com, read 16 October 2026
Returns: Text — developers.openai.com, read 16 October 2026
Open weights: Not confirmed: The maker’s pages reviewed do not state whether o3's weights are open or downloadable; no value is inferred.
Licence: Not confirmed: The maker’s pages reviewed do not name a licence for o3.
Context window: 200,000 tokens — developers.openai.com, read 16 October 2026
Longest answer: 100,000 tokens — developers.openai.com, read 16 October 2026
Knowledge cutoff: 1 June 2024 — developers.openai.com, read 16 October 2026
API price, input: $2.00 per 1M tokens — developers.openai.com, read 16 October 2026
API price, output: $8.00 per 1M tokens — developers.openai.com, read 16 October 2026
Where: API — developers.openai.com, read 16 October 2026
Parameters: Not confirmed: The maker’s pages reviewed do not publish a parameter count for o3.
Model card: Not confirmed: two readings disagree: https://cdn.openai.com/pdf/2221c875-02dc-4789-800b-e7758f3722c1/o3-and-o4-mini-system-card.pdf and https://openai.com/index/o3-o4-mini-system-card/

Benchmarks

Measured by others, not by the maker: each score with the name the measurer gives the model and the setting it ran, its day and its licence.

Arena

Text Arena, o3-2025-04-16: 1,432 (1,428–1,435, 58,908 votes), published 15 October 2026
Vision Arena, o3-2025-04-16: 1,216 (1,209–1,222, 45,599 votes), published 9 October 2026

Arena’s leaderboard dataset (lmarena-ai/leaderboard-dataset on Hugging Face), CC BY 4.0: ratings from people’s votes between two anonymous models, as Arena publishes them. Data · CC BY 4.0

Epoch AI

Epoch Capabilities Index, o3: 146.9 (145.0–148.7), as of 19 October 2026
GPQA Diamond, o3-2025-04-16_high: 81.8% (± 2.1), run 16 April 2025
GPQA Diamond, o3-2025-04-16_medium: 80.8% (± 2.8), run 7 August 2026
GPQA Diamond, o3-2025-04-16_low: 79.8% (± 2.9), run 15 July 2026
FrontierMath, tiers 1–3, o3-2025-04-16_high: 33.3% (± 2.8), run 27 August 2026
FrontierMath, tiers 1–3, o3-2025-04-16_medium: 29.8% (± 2.7), run 27 August 2026
FrontierMath, tiers 1–3, o3-2025-04-16_low: 19.3% (± 2.3), run 27 August 2026
SWE-bench Verified, o3-2025-04-16_medium: 62.3% (± 2.2), run 12 February 2026
OTIS Mock AIME 2024–2025, o3-2025-04-16_medium: 84.4% (± 5.5), run 7 August 2026
OTIS Mock AIME 2024–2025, o3-2025-04-16_high: 83.9% (± 4.4), run 16 April 2025
OTIS Mock AIME 2024–2025, o3-2025-04-16_low: 60.0% (± 7.4), run 15 July 2026
SimpleQA Verified, o3-2025-04-16_high: 49.4% (± 1.6), run 27 August 2026

Epoch AI, ‘Capabilities & benchmarking’, epoch.ai/benchmarks, CC BY 4.0: Epoch AI’s own runs and its Capabilities Index. Data · CC BY 4.0

Questions

When was o3 released?

OpenAI released o3 on 16 April 2025.

Is o3 still available?

It is deprecated: OpenAI has announced the date it will retire it.

What is the context window of o3?

The context window of o3 is 200,000 tokens, as OpenAI prints it.

How much does the o3 API cost?

On the standard tier, o3 costs $2.00 per 1M tokens for input and $8.00 per 1M tokens for output, as OpenAI lists it.

What does o3 take and return?

o3 takes text, image and returns text.

What is the knowledge cutoff of o3?

The knowledge cutoff of o3 is 1 June 2024.

Sources

Introducing OpenAI o3 and o4-mini (read 16 October 2026)
o3 Model | OpenAI API (read 16 October 2026)
Deprecations | OpenAI API (read 16 October 2026)
OpenAI o3 and o4-mini System Card (read 16 October 2026)

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o3