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Comparison · 2 models · Updated Nov 2, 2026

Grok 4.1 Fast vs Claude Haiku 4.5

Grok 4.1 Fast comes out ahead, 66 to 47 on our weighted score, and it is the cheaper option too.

  1. Our pick

    xAI

    Grok 4.1 Fast

    Released Nov 19, 2025

    66/100
    • ECI—
    • Price$0.20 / $0.50
    • Context2M
  2. Anthropic

    Claude Haiku 4.5

    Released Oct 15, 2025

    47/100
    • ECI142.2
    • Price$1.00 / $5.00
    • Context200K
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01 — Verdict

Grok 4.1 Fast is our pick

Grok 4.1 Fast is the better all-round choice, scoring 66/100 against Claude Haiku 4.5 (47). It leads on price and context window. Claude Haiku 4.5 wins on inputs & features. 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 priceGrok 4.1 FastGrok 4.1 Fast $0.275 · Claude Haiku 4.5 $2.00 per 1M tokens (3:1 blend)
  • Longest contextGrok 4.1 FastGrok 4.1 Fast 2,000,000 · Claude Haiku 4.5 200,000 tokens
  • Widest inputsClaude Haiku 4.5Grok 4.1 Fast: Text, Images · Claude Haiku 4.5: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGrok 4.1 FastClaude Haiku 4.5
Price50%7334
Inputs & features30%5080
Context window20%7232
Overall100%66/10047/100

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.

Grok 4.1 Fast vs Claude Haiku 4.5 specifications side by side
SpecificationGrok 4.1 FastxAIClaude Haiku 4.5Anthropic
Capability
Capabilities Index (ECI)—142.2
ECI rank—#102 of 165
GPQA DiamondGraduate-level science questions—71.2%
OTIS Mock AIME 2024–2025Competition mathematics—66.7%
SimpleQA VerifiedShort factual questions—13.2%
Price per million tokens
Input$0.20 (best)$1.00
Output$0.50 (best)$5.00
Cached input—$0.10
Blended (3:1)$0.275 (best)$2.00
Long-context rateSame rateSame rate
Price sourceMedian of 6 providersOfficial Anthropic API
Limits
Context window2,000,000 tokens (best)200,000 tokens
Max output30,000 tokens64,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoYes
AudioNoNo
VideoNoNo
ReasoningNoYes
Tool callingYesYes
Structured outputNoYes
Availability
WeightsProprietaryProprietary
API model ID—claude-haiku-4-5
API providers848 (best)
ReleasedNov 19, 2025Oct 15, 2025
Knowledge cutoff—Feb 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.

  • Grok 4.1 Fast$3.00
  • Claude Haiku 4.5$20.00
04 — Questions

Which should you choose?

Which is better: Grok 4.1 Fast or Claude Haiku 4.5?

Grok 4.1 Fast is the better all-round choice, scoring 66/100 against Claude Haiku 4.5 (47). It leads on price and context window. Claude Haiku 4.5 wins on inputs & features. 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, Grok 4.1 Fast or Claude Haiku 4.5?

Grok 4.1 Fast is cheaper at $0.20 input / $0.50 output per million tokens (median across 6 API providers). 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 $0.275 per million tokens for Grok 4.1 Fast versus $2.00 for Claude Haiku 4.5 (7.3× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. Grok 4.1 Fast has not been scored yet and Claude Haiku 4.5 has an ECI of 142.2.

Which is better for coding?

There are no published SWE-bench Verified results for Grok 4.1 Fast and Claude Haiku 4.5 yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Both support tool calling for agent workflows.

Which has the bigger context window?

Grok 4.1 Fast has the largest context window at 2,000,000 tokens, against 200,000 for Claude Haiku 4.5. Maximum output per response: Grok 4.1 Fast up to 30,000, Claude Haiku 4.5 up to 64,000 tokens.

Which can read images, PDFs, audio or video?

Grok 4.1 Fast accepts text and images; 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. Grok 4.1 Fast and Claude Haiku 4.5 are proprietary and only available through APIs and apps.

Which is newer?

Grok 4.1 Fast is the newest, released Nov 19, 2025. Claude Haiku 4.5 came out Oct 15, 2025. Knowledge cutoff: 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 Nov 2, 2026.