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Comparison · 3 models · Updated Oct 4, 2026

o3-pro vs Claude Opus 4 vs Pixtral 12B

Pixtral 12B comes out ahead, 64 to 27 and 27 on our weighted score, and it is the cheaper option too.

  1. OpenAI

    o3-pro

    Released Jun 10, 2025

    27/100
    • ECI147.4
    • Price$20.00 / $80.00
    • Context200K
    Full specs Remove o3-pro

  2. Anthropic

    Claude Opus 4

    Released May 22, 2025

    27/100
    • ECI142.7
    • Price$15.00 / $75.00
    • Context200K
    Full specs Remove Claude Opus 4
  3. Our pick

    Mistral AI

    Pixtral 12B

    Released Sep 1, 2024

    64/100
    • ECI—
    • Price$0.15 / $0.15
    • Context128K
    Full specs Remove Pixtral 12B
01 — Verdict

Pixtral 12B is our pick

Pixtral 12B is the better all-round choice, scoring 64/100 against o3-pro (27) and Claude Opus 4 (27). It leads on price. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

  • CapabilityNot enough dataNo independent benchmark covers every model here yet
  • Lowest pricePixtral 12BPixtral 12B $0.15 · Claude Opus 4 $30.00 · o3-pro $35.00 per 1M tokens (3:1 blend)
  • Longest contexto3-pro and Claude Opus 4o3-pro 200,000 · Claude Opus 4 200,000 · Pixtral 12B 128,000 tokens
  • Widest inputsClaude Opus 4o3-pro: Text, Images · Claude Opus 4: Text, Images, PDFs · Pixtral 12B: Text, Images
  • Self-hostingPixtral 12BPublishes downloadable weights
How the score is built
MeasureWeighto3-proClaude Opus 4Pixtral 12B
Price50%0089
Inputs & features30%707050
Context window20%323224
Overall100%27/10027/10064/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

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

o3-pro vs Claude Opus 4 vs Pixtral 12B specifications side by side
Specificationo3-proOpenAIClaude Opus 4AnthropicPixtral 12BMistral AI
Capability
Capabilities Index (ECI)147.4 (best)142.7—
ECI rank#60 of 148 (best)#87 of 148—
GPQA DiamondGraduate-level science questions—76.3%—
OTIS Mock AIME 2024–2025Competition mathematics—64.4%—
SWE-bench VerifiedFixing real GitHub issues—70.7%—
Price per million tokens
Input$20.00$15.00$0.15 (best)
Output$80.00$75.00$0.15 (best)
Cached input———
Blended (3:1)$35.00$30.00$0.15 (best)
Long-context rateSame rateSame rateSame rate
Price sourceOfficial OpenAI APIMedian of 5 providersOfficial Mistral API
Limits
Context window200,000 tokens (best)200,000 tokens (best)128,000 tokens
Max output100,000 tokens32,000 tokens128,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsNoYesNo
AudioNoNoNo
VideoNoNoNo
ReasoningYeslow · medium · highYesNo
Tool callingYesYesYes
Structured outputYesNoNo
Availability
WeightsProprietaryProprietaryOpen
API model IDo3-pro—pixtral-12b
API providers6 (best)54
ReleasedJun 10, 2025May 22, 2025Sep 1, 2024
Knowledge cutoffMay 2024Mar 31, 2025Sep 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
  • Claude Opus 4$300.00
  • Pixtral 12B$1.80
04 — Questions

Which should you choose?

Which is better: o3-pro, Claude Opus 4 or Pixtral 12B?

Pixtral 12B is the better all-round choice, scoring 64/100 against o3-pro (27) and Claude Opus 4 (27). It leads on price. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

Which is cheaper, o3-pro, Claude Opus 4 or Pixtral 12B?

Pixtral 12B is cheaper at $0.15 input / $0.15 output per million tokens (official Mistral API price). Claude Opus 4 costs $15.00 input / $75.00 output per million tokens (median across 5 API providers); 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 $0.15 per million tokens for Pixtral 12B versus $30.00 for Claude Opus 4 (200× as much) and $35.00 for o3-pro (233× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. o3-pro has an ECI of 147.4, Claude Opus 4 has an ECI of 142.7 and Pixtral 12B has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for o3-pro and Pixtral 12B yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. All three support tool calling for agent workflows.

Which has the bigger context window?

o3-pro and Claude Opus 4 have the largest context windows (200,000 and 200,000 tokens), against 128,000 for Pixtral 12B. Maximum output per response: o3-pro up to 100,000, Claude Opus 4 up to 32,000, Pixtral 12B up to 128,000 tokens.

Which can read images, PDFs, audio or video?

o3-pro accepts text and images; Claude Opus 4 accepts text, images and PDFs; Pixtral 12B accepts text and images. Claude Opus 4 handles the widest range of inputs.

Are any of these open source?

Pixtral 12B publishes its weights and can be self-hosted; o3-pro and Claude Opus 4 is proprietary.

Which is newer?

o3-pro is the newest, released Jun 10, 2025. Claude Opus 4 came out May 22, 2025; Pixtral 12B came out Sep 1, 2024. Knowledge cutoff: o3-pro May 2024, Claude Opus 4 Mar 31, 2025, Pixtral 12B Sep 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.

05 — Keep comparing

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