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Claude 3 Sonnet vs Grok-1.5

Claude 3 Sonnet and Grok-1.5 are closely matched at 1.7 and -2.6 on the LLM Stats Score.

Anthropic · xAI · Updated for 2026

Which is better?

Claude 3 Sonnet and Grok-1.5 are closely matched on the overall LLM Stats Score at 1.7 and -2.6.

The models split the 6 individual benchmarks reported for both models evenly.

Based on current LLM Stats indexes, shared benchmarks, 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.

Core performance indexes
1.7
#318
-2.6
#339
1.7
#309
-2.2
#329
-1.4
#246
-0.9
#245
Cost, coverage & limits
Benchmark wins
3 of 6
3 of 6
Input price
$3.00 / M
— / M
Output price
$15.00 / M
— / M
Context window
200,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

3 shared
Index
Claude 3 Sonnet
Grok-1.5
7.4#264
4.9#277
3.1#180
4.7#174
3.1#168
4.7#158
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

11 reported for Claude 3 Sonnet · 9 for Grok-1.5

6 shared

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.

Tue Sep 15 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground 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
Tue Sep 15 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

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

2.5 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?

Claude 3 Sonnet and Grok-1.5 are closely matched on the LLM Stats Score at 1.7 and -2.6. 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 capability indexes, individual benchmarks, pricing, and limits 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 LLM Stats Score (1.7 vs -2.6), 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.