How much does o3 cost?

o3 costs $2.00 per million input tokens and $8.00 per million output tokens, using the list price from OpenAI as of 26 Oct 2026. That is about $0.60 for 100 chats of about 1,000 tokens in and 500 tokens back. Confirm on the maker's site before you buy, because prices change.

What is the context window of o3?

o3 has a context window of 200K tokens, roughly 150,000 words of text read at once. A single answer can be up to 100K tokens long.

We list o3 as closed: it is used through its maker's apps or API and its weights are not published (Epoch AI lists its access as "API access").

How good is o3 compared with other AI models?

On the Epoch Capabilities Index, o3 scores 146.7 (likely range 144.8 to 148.5), which ranks 76 of 270 models we track. On Arena's human-vote text board it is ranked 82 of 166. Scores close together are a tie in practice.

How does o3 compare with Claude Sonnet 4.5?

On quality, neither model leads clearly across the 11 measures both have. 3 measures are too close to call. o3 costs about 42% less than Claude Sonnet 4.5 on a blended price of $3.50 against $6.00 per million tokens. See the full comparison for every measure.

How current are these numbers for o3?

The newest data on this page is dated 26 Oct 2026. Scores come from Epoch AI and Arena, prices from the open LiteLLM price list.

AI Rankings

o3: Score, Price and Context Window

Where o3 from OpenAI ranks, what it costs and how much text it can read, in plain numbers with the sources.

Data updated 26 Oct 2026

OpenAI
Closed weights
Released Apr 2025

Its score range overlaps with Claude Sonnet 4.5, the model just above it, so a small gap in rank is not a meaningful difference.

Key facts

Overall score: 146.7; Rank 76 of 270. Likely range 144.8 to 148.5.
Human preference: chat: 1432; Rank 82 of 166. 58,894 votes.
Human preference: coding: 1460; Rank 91 of 166. 11,581 votes.
Human preference: images: 1216; Rank 58 of 85. 45,567 votes.
Price per million tokens: $2.00 in / $8.00 out; Blended $3.50. Cached input $0.50. List price from OpenAI, checked 26 Oct 2026.
Context window: 200K tokens; About 150,000 words at once. One answer up to 100K tokens.
Weights: Closed; Used through the maker's apps or API (Epoch AI: API access).

Features listed by the price list: Image input, PDF input, Tool use, Reasoning, Web search, Prompt caching, Structured output.

Try itChatGPT in our AI tools directoryOpenAI's AI assistant for writing, coding, research, file analysis, and connected work across chats and projects.

How o3 stacks up

Each strip shows every model we track as faint bars. The dot is this model. Better is always to the right, even for price.

o3 compared with all models we trackOverall capability: 146.7. Better than 72% of the other 269 models. Human preference: chat: 1432. Better than 50% of the other 165 models. Human preference: coding: 1460. Better than 44% of the other 165 models. Human preference: images: 1216. Better than 32% of the other 84 models. Price: $3.50 per 1M. Cheaper than 26% of the other 200 priced models. Context window: 200K tokens. Larger context window than 39% of the other 198 models.

Overall capability146.7
Better than 72% of the other 269 modelsUpper half
Epoch Capabilities Index: one score that combines many tests.
Human preference: chat1432
Better than 50% of the other 165 modelsUpper half
How often people pick its answers over another model's on Arena.
Human preference: coding1460
Better than 44% of the other 165 models
How often people pick its answers to coding questions on Arena.
Human preference: images1216
Better than 32% of the other 84 models
How often people pick its answers about pictures on Arena.
Price$3.50 per 1M
Cheaper than 26% of the other 200 priced models
Blended price per million tokens. Lower is better, so the cheapest models sit on the right.
Context window200K tokens
Larger context window than 39% of the other 198 models
How much text it can read at once. Bigger suits long documents.

Compared with the other published models that have each measure. Data updated 26 Oct 2026.

Where o3 ranks

Leaderboards it appears on, best placing first.

See all leaderboards

Test results

Each test checks one kind of skill. Place shows where it stands among the models that took that test.

Aider Polyglot
225 coding exercises in six programming languages. The AI edits the code files and the exercise's tests decide pass or fail.
81.3%
Place 4 of 46
SimpleQA Verified
Short factual questions that each have one correct answer. It measures how often a model gets facts right.
49.4%
Place 28 of 82
OTIS Mock AIME
Maths competition problems in the style of the US AIME exam, from the 2024 and 2025 sets. Every answer is a whole number.
84.4%
Place 77 of 174
tied with 2 others
SimpleBench
Everyday common-sense and trick questions that most people answer correctly but AI models often get wrong.
53.1%
Place 36 of 80
GPQA Diamond
Very hard multiple-choice science questions in biology, physics and chemistry, written by experts and designed so a quick web search does not give the answer.
81.8%
Place 83 of 183
tied with 1 other
Humanity's Last Exam
A large set of very hard, expert-written questions across many subjects, built to stay difficult for top AI models.
20.3%
Place 20 of 41
ARC-AGI-2
Visual puzzles where the AI must work out a new rule from a few examples and apply it. They test picking up a new idea quickly, not recalling facts.
6.5%
Place 54 of 86
FrontierMath (Tiers 1-3)
Original, very hard maths problems written by mathematicians. Each has an exact answer and the problems are kept private so models cannot have memorised them. This is the Tiers 1 to 3 set, version 2.
33.3%
Place 65 of 87
tied with 1 other
SWE-bench Verified
Real bug reports from open-source software projects. The AI has to change the code so the project's own tests pass. The tasks were checked by people.
62.3%
Place 27 of 32

What it costs in everyday terms

List prices turned into amounts you can picture. Real bills depend on how you use it.

100 chats: $0.60; Cost of 100 chats assumes each chat sends 1,000 tokens (about 750 words) and gets 500 tokens (about 375 words) back.
A 300-page book: $0.20; Cost to read a 300-page book assumes about 100,000 input tokens and no reply. A real book varies with page size and language.
Blended price: $3.50 per 1M; Three parts input to one part output. Our own calculation for comparing models.

Similar models

Models from other makers with a similar overall score.

Learn more

Questions about o3

How much does o3 cost?: o3 costs $2.00 per million input tokens and $8.00 per million output tokens, using the list price from OpenAI as of 26 Oct 2026. That is about $0.60 for 100 chats of about 1,000 tokens in and 500 tokens back. Confirm on the maker's site before you buy, because prices change.
What is the context window of o3?: o3 has a context window of 200K tokens, roughly 150,000 words of text read at once. A single answer can be up to 100K tokens long.
Is o3 open source?: We list o3 as closed: it is used through its maker's apps or API and its weights are not published (Epoch AI lists its access as "API access").
How good is o3 compared with other AI models?: On the Epoch Capabilities Index, o3 scores 146.7 (likely range 144.8 to 148.5), which ranks 76 of 270 models we track. On Arena's human-vote text board it is ranked 82 of 166. Scores close together are a tie in practice.
How does o3 compare with Claude Sonnet 4.5?: On quality, neither model leads clearly across the 11 measures both have. 3 measures are too close to call. o3 costs about 42% less than Claude Sonnet 4.5 on a blended price of $3.50 against $6.00 per million tokens. See the full comparison for every measure.
How current are these numbers for o3?: The newest data on this page is dated 26 Oct 2026. Scores come from Epoch AI and Arena, prices from the open LiteLLM price list.

Where this data comes from

Epoch AI: Benchmark data: Epoch AI, 'Capabilities & benchmarking', epoch.ai/benchmarks (CC BY 4.0). We match models across sources, rank them and show them in charts. Scores are not changed. Epoch AI does not endorse this site.
Arena (formerly LMArena): Human-preference ratings: Arena (arena.ai) leaderboard dataset, CC BY 4.0. We keep the latest published ratings, match them to models from other sources and rank them. Ratings are not changed. Arena does not endorse this site.
LiteLLM model price list: Prices and context windows: LiteLLM model price list (github.com/BerriAI/litellm, MIT licence). We use the model maker's own price entry when there is one. Prices change often, so always confirm on the maker's site before you buy.

Newest data on this page: 26 Oct 2026. Prices are list prices and change often, so confirm on the maker's site before you buy. Sponsors never change a score or an order. How we calculate this · Report a mistake