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Comparison · 2 models · Updated Oct 4, 2026

o3-pro vs o3

o3 comes out ahead, 58 to 51 on our weighted score, and it is the cheaper option too.

  1. OpenAI

    o3-pro

    Released Jun 10, 2025

    51/100
    • ECI147.4
    • Price$20.00 / $80.00
    • Context200K
  2. Our pick

    OpenAI

    o3

    Released Apr 16, 2025

    58/100
    • ECI146.9
    • Price$2.00 / $8.00
    • Context200K
  3. Add a model

    Make it a three-way comparison.

01 — Verdict

o3 is our pick

o3 is the better all-round choice, scoring 58/100 against o3-pro (51). It leads on price and inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • Capabilityo3-proCapabilities Index (ECI): o3-pro 147.4 · o3 146.9
  • Lowest priceo3o3 $3.50 · o3-pro $35.00 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameo3-pro 200,000 · o3 200,000 tokens
  • Widest inputso3o3-pro: Text, Images · o3: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeighto3-proo3
CapabilityCapabilities Index (ECI)50%7574
Price25%024
Inputs & features15%7080
Context window10%3232
Overall100%51/10058/100
02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

o3-pro vs o3 specifications side by side
Specificationo3-proOpenAIo3OpenAI
Capability
Capabilities Index (ECI)147.4 (best)146.9
ECI rank#60 of 148 (best)#63 of 148
GPQA DiamondGraduate-level science questions—81.8%
FrontierMath Tiers 1–3Research-level mathematics—33.3%
OTIS Mock AIME 2024–2025Competition mathematics—84.4%
SWE-bench VerifiedFixing real GitHub issues—62.3%
SimpleQA VerifiedShort factual questions—49.4%
Price per million tokens
Input$20.00$2.00 (best)
Output$80.00$8.00 (best)
Cached input—$0.50
Blended (3:1)$35.00$3.50 (best)
Long-context rateSame rateSame rate
Price sourceOfficial OpenAI APIOfficial OpenAI API
Limits
Context window200,000 tokens200,000 tokens
Max output100,000 tokens100,000 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoYes
AudioNoNo
VideoNoNo
ReasoningYeslow · medium · highYeslow · medium · high
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDo3-proo3
API providers618 (best)
ReleasedJun 10, 2025Apr 16, 2025
Knowledge cutoffMay 2024May 2024
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • o3-pro$360.00
  • o3$36.00
04 — Questions

Which should you choose?

Which is better: o3-pro or o3?

o3 is the better all-round choice, scoring 58/100 against o3-pro (51). It leads on price and inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, o3-pro or o3?

o3 is cheaper at $2.00 input / $8.00 output per million tokens (official OpenAI API price). o3-pro costs $20.00 input / $80.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $3.50 per million tokens for o3 versus $35.00 for o3-pro (10× as much).

Which scores higher on benchmarks?

o3-pro scores higher on the Capabilities Index (ECI): o3-pro 147.4 (#60 of 148) and o3 146.9 (#63 of 148). The confidence ranges of the top two overlap (145.8–149.7 vs 144.9–148.6), so treat the gap as small.

Which is better for coding?

There are no published SWE-bench Verified results for o3-pro yet, so there is no like-for-like coding score. On overall capability, o3-pro leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.

Which has the bigger context window?

o3-pro and o3 share the same 200,000-token context window. Maximum output per response: o3-pro up to 100,000, o3 up to 100,000 tokens.

Which can read images, PDFs, audio or video?

o3-pro accepts text and images; o3 accepts text, images and PDFs. o3 handles the widest range of inputs.

Are any of these open source?

No. o3-pro and o3 are proprietary and only available through APIs and apps.

Which is newer?

o3-pro is the newest, released Jun 10, 2025. o3 came out Apr 16, 2025. Knowledge cutoff: o3-pro May 2024, o3 May 2024.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.