Model Comparison

Claude Sonnet 4.5 vs Grok-2Which is better in 2026?

Claude Sonnet 4.5 significantly outperforms across most benchmarks. Grok-2 is 1.5x cheaper per token.

Verdict: Claude Sonnet 4.5 vs Grok-2 — which is better?

Claude Sonnet 4.5 (by Anthropic) and Grok-2 (by xAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Claude Sonnet 4.5 outperforms in 1 benchmarks (GPQA), while Grok-2 is better at 0 benchmarks. Claude Sonnet 4.5 significantly outperforms across most benchmarks.

On price, Grok-2 is roughly 1.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Sonnet 4.5 also accepts a larger context window (200,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Claude Sonnet 4.5 if…

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • you process long inputs — it offers a 200,000 token context window
  • you want the most recent training data — it shipped Sep 2025

Choose Grok-2 if…

  • cost matters — it's about 1.5x cheaper per token

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

Claude Sonnet 4.5 outperforms in 1 benchmarks (GPQA), while Grok-2 is better at 0 benchmarks.

Claude Sonnet 4.5 significantly outperforms across most benchmarks.

Sat Jun 27 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Grok-2 costs less

For input processing, Claude Sonnet 4.5 ($3.00/1M tokens) is 1.5x more expensive than Grok-2 ($2.00/1M tokens).

For output processing, Claude Sonnet 4.5 ($15.00/1M tokens) is 1.5x more expensive than Grok-2 ($10.00/1M tokens).

In conclusion, Claude Sonnet 4.5 is more expensive than Grok-2.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Sat Jun 27 2026 • llm-stats.com
Anthropic
Claude Sonnet 4.5
Input tokens$3.00
Output tokens$15.00
Best providerAnthropic
xAI
Grok-2
Input tokens$2.00
Output tokens$10.00
Best providerxAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Claude Sonnet 4.5 accepts 200,000 input tokens compared to Grok-2's 128,000 tokens. Claude Sonnet 4.5 can generate longer responses up to 64,000 tokens, while Grok-2 is limited to 8,000 tokens.

Anthropic
Claude Sonnet 4.5
Input200,000 tokens
Output64,000 tokens
xAI
Grok-2
Input128,000 tokens
Output8,000 tokens
Sat Jun 27 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Sonnet 4.5 and Grok-2 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Sonnet 4.5

Text
Images
Audio
Video

Grok-2

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Sonnet 4.5

Proprietary

Closed source

Grok-2

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Sonnet 4.5 was released on 2025-09-29, while Grok-2 was released on 2024-08-13.

Claude Sonnet 4.5 is 14 months newer than Grok-2.

Claude Sonnet 4.5

Sep 29, 2025

9 months ago

1.1yr newer
Grok-2

Aug 13, 2024

1.9 years ago

Knowledge Cutoff

When training data ends

Claude Sonnet 4.5 has a documented knowledge cutoff of 2025-01-31, while Grok-2's cutoff date is not specified.

We can confirm Claude Sonnet 4.5's training data extends to 2025-01-31, but cannot make a direct comparison without Grok-2's cutoff date.

Claude Sonnet 4.5

Jan 2025

Grok-2

—

Provider Availability

Claude Sonnet 4.5 is available from Anthropic. Grok-2 is available from xAI.

Claude Sonnet 4.5

anthropic logo
Anthropic
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M

Grok-2

xai logo
xAI
Input Price:Input: $2.00/1MOutput Price:Output: $10.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Larger context window (200,000 tokens)
Higher GPQA score (83.4% vs 56.0%)
xAI
Less expensive input tokens
Less expensive output tokens

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Sonnet 4.5 and Grok-2 side-by-side, then vote on the output you prefer.

Claude Sonnet 4.5
✓ Preferred
Grok-2
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Sonnet 4.5
xAI
Grok-2

FAQ

Common questions about Claude Sonnet 4.5 vs Grok-2.

Which is better, Claude Sonnet 4.5 or Grok-2?

Claude Sonnet 4.5 significantly outperforms across most benchmarks. Claude Sonnet 4.5 is made by Anthropic and Grok-2 is made by xAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Sonnet 4.5 compare to Grok-2 in benchmarks?

Claude Sonnet 4.5 scores MMMLU: 89.1%, AIME 2025: 87.0%, TAU-bench Retail: 86.2%, GPQA: 83.4%, MMMUval: 77.8%. Grok-2 scores DocVQA: 93.6%, HumanEval: 88.4%, MMLU: 87.5%, MATH: 76.1%, MMLU-Pro: 75.5%.

Is Claude Sonnet 4.5 cheaper than Grok-2?

Grok-2 is 1.5x cheaper for input tokens. Claude Sonnet 4.5 costs $3.00/M input and $15.00/M output via anthropic. Grok-2 costs $2.00/M input and $10.00/M output via xai.

What are the context window sizes for Claude Sonnet 4.5 and Grok-2?

Claude Sonnet 4.5 supports 200K tokens and Grok-2 supports 128K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Sonnet 4.5 and Grok-2?

Key differences include context window (200K vs 128K), input pricing ($3.00 vs $2.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Sonnet 4.5 and Grok-2?

Claude Sonnet 4.5 is developed by Anthropic and Grok-2 is developed by xAI.

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