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Comparison · 2 models · Updated Oct 4, 2026

o3-mini vs Claude Haiku 4.5

Claude Haiku 4.5 comes out ahead, 58 to 52 on our weighted score.

  1. OpenAI

    o3-mini

    Released Jan 31, 2025Deprecated

    52/100
    • ECI140.3
    • Price$1.10 / $4.40
    • Context200K
    Full specs Remove o3-mini
  2. 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

  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-mini (52). It leads on capability and inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityClaude Haiku 4.5Capabilities Index (ECI): Claude Haiku 4.5 142.4 · o3-mini 140.3
  • Lowest priceo3-minio3-mini $1.93 · Claude Haiku 4.5 $2.00 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameo3-mini 200,000 · Claude Haiku 4.5 200,000 tokens
  • Widest inputsClaude Haiku 4.5o3-mini: Text · Claude Haiku 4.5: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeighto3-miniClaude Haiku 4.5
CapabilityCapabilities Index (ECI)50%6669
Price25%3636
Inputs & features15%4580
Context window10%3232
Overall100%52/10058/100
02 — Side by side

Every spec in one table

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

o3-mini vs Claude Haiku 4.5 specifications side by side
Specificationo3-miniOpenAIClaude Haiku 4.5Anthropic
Capability
Capabilities Index (ECI)140.3142.4 (best)
ECI rank#98 of 148#90 of 148 (best)
GPQA DiamondGraduate-level science questions77.0% (best)71.2%
FrontierMath Tiers 1–3Research-level mathematics18.6%—
OTIS Mock AIME 2024–2025Competition mathematics76.9% (best)66.7%
SimpleQA VerifiedShort factual questions15.3% (best)13.2%
Price per million tokens
Input$1.10$1.00 (best)
Output$4.40 (best)$5.00
Cached input$0.55$0.10 (best)
Blended (3:1)$1.93 (best)$2.00
Long-context rateSame rateSame rate
Price sourceOfficial OpenAI APIOfficial Anthropic API
Limits
Context window200,000 tokens200,000 tokens
Max output100,000 tokens (best)64,000 tokens
Inputs and features
TextYesYes
ImagesNoYes
PDFsNoYes
AudioNoNo
VideoNoNo
ReasoningYeslow · medium · highYes
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDo3-miniclaude-haiku-4-5
API providers1534 (best)
ReleasedJan 31, 2025Oct 15, 2025
Knowledge cutoffMay 2024Feb 28, 2025
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-mini$19.80
  • Claude Haiku 4.5$20.00
04 — Questions

Which should you choose?

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

Claude Haiku 4.5 is the better all-round choice, scoring 58/100 against o3-mini (52). It leads on capability and inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

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

o3-mini is cheaper at $1.10 input / $4.40 output per million tokens (official OpenAI API price). Claude Haiku 4.5 costs $1.00 input / $5.00 output per million tokens (official Anthropic API price). At a typical mix of three input tokens to one output token, that is $1.93 per million tokens for o3-mini versus $2.00 for Claude Haiku 4.5 (1× as much).

Which scores higher on benchmarks?

Claude Haiku 4.5 scores higher on the Capabilities Index (ECI): Claude Haiku 4.5 142.4 (#90 of 148) and o3-mini 140.3 (#98 of 148). The confidence ranges of the top two overlap (139.5–144.3 vs 137.4–141.9), so treat the gap as small. On individual benchmarks: GPQA Diamond — o3-mini 77.0%, Claude Haiku 4.5 71.2%; OTIS Mock AIME 2024–2025 — o3-mini 76.9%, Claude Haiku 4.5 66.7%; SimpleQA Verified — o3-mini 15.3%, Claude Haiku 4.5 13.2%.

Which is better for coding?

There are no published SWE-bench Verified results for o3-mini and Claude Haiku 4.5 yet, so there is no like-for-like coding score. On overall capability, Claude Haiku 4.5 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-mini and Claude Haiku 4.5 share the same 200,000-token context window. Maximum output per response: o3-mini up to 100,000, Claude Haiku 4.5 up to 64,000 tokens.

Which can read images, PDFs, audio or video?

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

Are any of these open source?

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

Which is newer?

Claude Haiku 4.5 is the newest, released Oct 15, 2025. o3-mini came out Jan 31, 2025. Knowledge cutoff: o3-mini May 2024, Claude Haiku 4.5 Feb 28, 2025.

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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