ZMIME
Comparison · 2 models · Updated Oct 4, 2026

Claude Sonnet 4 vs Claude Haiku 4.5

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

  1. Anthropic

    Claude Sonnet 4

    Released May 22, 2025

    51/100
    • ECI141.7
    • Price$3.00 / $15.00
    • Context200K
    Full specs Remove Claude Sonnet 4
  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 Claude Sonnet 4 (51). It leads on price 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 · Claude Sonnet 4 141.7
  • Lowest priceClaude Haiku 4.5Claude Haiku 4.5 $2.00 · Claude Sonnet 4 $6.00 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameClaude Sonnet 4 200,000 · Claude Haiku 4.5 200,000 tokens
  • Widest inputsSame inputsClaude Sonnet 4: Text, Images, PDFs · Claude Haiku 4.5: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightClaude Sonnet 4Claude Haiku 4.5
CapabilityCapabilities Index (ECI)50%6869
Price25%1336
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.

Claude Sonnet 4 vs Claude Haiku 4.5 specifications side by side
SpecificationClaude Sonnet 4AnthropicClaude Haiku 4.5Anthropic
Capability
Capabilities Index (ECI)141.7142.4 (best)
ECI rank#94 of 148#90 of 148 (best)
GPQA DiamondGraduate-level science questions79.2% (best)71.2%
OTIS Mock AIME 2024–2025Competition mathematics71.1% (best)66.7%
SimpleQA VerifiedShort factual questions—13.2%
Price per million tokens
Input$3.00$1.00 (best)
Output$15.00$5.00 (best)
Cached input—$0.10
Blended (3:1)$6.00$2.00 (best)
Long-context rateSame rateSame rate
Price sourceMedian of 9 providersOfficial Anthropic API
Limits
Context window200,000 tokens200,000 tokens
Max output64,000 tokens64,000 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesYes
AudioNoNo
VideoNoNo
ReasoningYesYes
Tool callingYesYes
Structured outputNoYes
Availability
WeightsProprietaryProprietary
API model ID—claude-haiku-4-5
API providers934 (best)
ReleasedMay 22, 2025Oct 15, 2025
Knowledge cutoffMar 31, 2025Feb 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.

  • Claude Sonnet 4$60.00
  • Claude Haiku 4.5$20.00
04 — Questions

Which should you choose?

Which is better: Claude Sonnet 4 or Claude Haiku 4.5?

Claude Haiku 4.5 is the better all-round choice, scoring 58/100 against Claude Sonnet 4 (51). It leads on price and inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Claude Sonnet 4 or Claude Haiku 4.5?

Claude Haiku 4.5 is cheaper at $1.00 input / $5.00 output per million tokens (official Anthropic API price). Claude Sonnet 4 costs $3.00 input / $15.00 output per million tokens (median across 9 API providers). 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 $6.00 for Claude Sonnet 4 (3× 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 Claude Sonnet 4 141.7 (#94 of 148). The confidence ranges of the top two overlap (139.5–144.3 vs 139.2–142.9), so treat the gap as small. On individual benchmarks: GPQA Diamond — Claude Sonnet 4 79.2%, Claude Haiku 4.5 71.2%; OTIS Mock AIME 2024–2025 — Claude Sonnet 4 71.1%, Claude Haiku 4.5 66.7%.

Which is better for coding?

There are no published SWE-bench Verified results for Claude Sonnet 4 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?

Claude Sonnet 4 and Claude Haiku 4.5 share the same 200,000-token context window. Maximum output per response: Claude Sonnet 4 up to 64,000, Claude Haiku 4.5 up to 64,000 tokens.

Which can read images, PDFs, audio or video?

Claude Sonnet 4 accepts text, images and PDFs; Claude Haiku 4.5 accepts text, images and PDFs. They handle the same number of input types.

Are any of these open source?

No. Claude Sonnet 4 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. Claude Sonnet 4 came out May 22, 2025. Knowledge cutoff: Claude Sonnet 4 Mar 31, 2025, 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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