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Comparison · 2 models · Updated Oct 4, 2026

Claude Haiku 4.5 vs o3-pro

Claude Haiku 4.5 comes out ahead, 58 to 51 on our weighted score, and it is the cheaper option too.

  1. Our pick

    Anthropic

    Claude Haiku 4.5

    Released Oct 15, 2025

    58/100
    • ECI142.4
    • Price$1.00 / $5.00
    • Context200K
    Full specs Remove Claude Haiku 4.5

  2. OpenAI

    o3-pro

    Released Jun 10, 2025

    51/100
    • ECI147.4
    • Price$20.00 / $80.00
    • Context200K
    Full specs Remove o3-pro

  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Claude Haiku 4.5 is our pick

Claude Haiku 4.5 is the better all-round choice, scoring 58/100 against o3-pro (51). It leads on price and inputs & features. o3-pro wins on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • Capabilityo3-proCapabilities Index (ECI): o3-pro 147.4 · Claude Haiku 4.5 142.4
  • Lowest priceClaude Haiku 4.5Claude Haiku 4.5 $2.00 · o3-pro $35.00 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameClaude Haiku 4.5 200,000 · o3-pro 200,000 tokens
  • Widest inputsClaude Haiku 4.5Claude Haiku 4.5: Text, Images, PDFs · o3-pro: Text, Images
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightClaude Haiku 4.5o3-pro
CapabilityCapabilities Index (ECI)50%6975
Price25%360
Inputs & features15%8070
Context window10%3232
Overall100%58/10051/100
02 — Side by side

Every spec in one table

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

Claude Haiku 4.5 vs o3-pro specifications side by side
SpecificationClaude Haiku 4.5Anthropico3-proOpenAI
Capability
Capabilities Index (ECI)142.4147.4 (best)
ECI rank#90 of 148#60 of 148 (best)
GPQA DiamondGraduate-level science questions71.2%—
OTIS Mock AIME 2024–2025Competition mathematics66.7%—
SimpleQA VerifiedShort factual questions13.2%—
Price per million tokens
Input$1.00 (best)$20.00
Output$5.00 (best)$80.00
Cached input$0.10—
Blended (3:1)$2.00 (best)$35.00
Long-context rateSame rateSame rate
Price sourceOfficial Anthropic APIOfficial OpenAI API
Limits
Context window200,000 tokens200,000 tokens
Max output64,000 tokens100,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesNo
AudioNoNo
VideoNoNo
ReasoningYesYeslow · medium · high
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDclaude-haiku-4-5o3-pro
API providers34 (best)6
ReleasedOct 15, 2025Jun 10, 2025
Knowledge cutoffFeb 28, 2025May 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.

  • Claude Haiku 4.5$20.00
  • o3-pro$360.00
04 — Questions

Which should you choose?

Which is better: Claude Haiku 4.5 or o3-pro?

Claude Haiku 4.5 is the better all-round choice, scoring 58/100 against o3-pro (51). It leads on price and inputs & features. o3-pro wins on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Claude Haiku 4.5 or o3-pro?

Claude Haiku 4.5 is cheaper at $1.00 input / $5.00 output per million tokens (official Anthropic 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 $2.00 per million tokens for Claude Haiku 4.5 versus $35.00 for o3-pro (18× as much).

Which scores higher on benchmarks?

o3-pro scores higher on the Capabilities Index (ECI): o3-pro 147.4 (#60 of 148) and Claude Haiku 4.5 142.4 (#90 of 148). Their confidence ranges do not overlap (145.8–149.7 vs 139.5–144.3), so the gap is a real one.

Which is better for coding?

There are no published SWE-bench Verified results for Claude Haiku 4.5 and 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?

Claude Haiku 4.5 and o3-pro share the same 200,000-token context window. Maximum output per response: Claude Haiku 4.5 up to 64,000, o3-pro up to 100,000 tokens.

Which can read images, PDFs, audio or video?

Claude Haiku 4.5 accepts text, images and PDFs; o3-pro accepts text and images. Claude Haiku 4.5 handles the widest range of inputs.

Are any of these open source?

No. Claude Haiku 4.5 and o3-pro are proprietary and only available through APIs and apps.

Which is newer?

Claude Haiku 4.5 is the newest, released Oct 15, 2025. o3-pro came out Jun 10, 2025. Knowledge cutoff: Claude Haiku 4.5 Feb 28, 2025, o3-pro 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.

05 — Keep comparing

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