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Claude 3 Sonnet vs Grok-1.5

Both models are evenly matched across the benchmarks.

Anthropic · xAI · Updated for 2026

Which is better?

Claude 3 Sonnet outperforms in 3 benchmarks (GPQA, GSM8k, MMLU-Pro), while Grok-1.5 is better at 3 benchmarks (HumanEval, MATH, MMLU). Both models are evenly matched across the benchmarks.

Based on current benchmark, pricing, and model metadata for 2026.

Choose Claude 3 Sonnet

  • you want predictable pricing at $3.00/M input and $15.00/M output

Choose Grok-1.5

  • you want the most recent training data — it shipped Mar 2024

At a glance

The differences that matter most.

Claude 3 Sonnet
Anthropic
Grok-1.5
xAI
Benchmark wins
3 of 6
3 of 6
Input price
$3.00 / M
— / M
Output price
$15.00 / M
— / M
Context window
200,000
—
Released
Feb 2024
Mar 2024
License
Proprietary
Proprietary

Performance Benchmarks

Comparative analysis across standard metrics

6 benchmarks

Claude 3 Sonnet outperforms in 3 benchmarks (GPQA, GSM8k, MMLU-Pro), while Grok-1.5 is better at 3 benchmarks (HumanEval, MATH, MMLU).

Both models are evenly matched across the benchmarks.

Wed Aug 26 2026 • llm-stats.com

Arena Performance

Playground indexes and blind preference scores

Context Window

Maximum input and output token capacity

Only Claude 3 Sonnet specifies input context (200,000 tokens). Only Claude 3 Sonnet specifies output context (200,000 tokens).

Anthropic
Claude 3 Sonnet
Input200,000 tokens
Output200,000 tokens
xAI
Grok-1.5
Input- tokens
Output- tokens
Wed Aug 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Claude 3 Sonnet supports multimodal inputs, whereas Grok-1.5 does not.

Claude 3 Sonnet can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude 3 Sonnet

Text
Images
Audio
Video

Grok-1.5

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 3 Sonnet

Proprietary

Closed source

Grok-1.5

Proprietary

Closed source

Release Timeline

When each model was launched

Claude 3 Sonnet was released on 2024-02-29, while Grok-1.5 was released on 2024-03-28.

Grok-1.5 is 1 month newer than Claude 3 Sonnet.

Claude 3 Sonnet

Feb 29, 2024

2.5 years ago

Grok-1.5

Mar 28, 2024

2.4 years ago

4w newer

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Claude 3 Sonnet and Grok-1.5 side-by-side, then vote on the output you prefer.

Claude 3 Sonnet
✓ Preferred
Grok-1.5
Open in Playground

FAQ

Common questions about Claude 3 Sonnet vs Grok-1.5.

Which is better, Claude 3 Sonnet or Grok-1.5?

Both models are evenly matched across the benchmarks. Claude 3 Sonnet is made by Anthropic and Grok-1.5 is made by xAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude 3 Sonnet compare to Grok-1.5 in benchmarks?

Claude 3 Sonnet scores ARC-C: 93.2%, GSM8k: 92.3%, HellaSwag: 89.0%, MGSM: 83.5%, BIG-Bench Hard: 82.9%. Grok-1.5 scores GSM8k: 90.0%, DocVQA: 85.6%, MMLU: 81.3%, HumanEval: 74.1%, MMMU: 53.6%.

What are the context window sizes for Claude 3 Sonnet and Grok-1.5?

Claude 3 Sonnet supports 200K tokens and Grok-1.5 supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude 3 Sonnet and Grok-1.5?

Key differences include multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude 3 Sonnet and Grok-1.5?

Claude 3 Sonnet is developed by Anthropic and Grok-1.5 is developed by xAI.

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