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Claude 3 Opus vs Grok-1.5

Claude 3 Opus leads the LLM Stats Score 9.9 to -2.6.

Anthropic · xAI · Updated for 2026

Which is better?

Claude 3 Opus leads the overall LLM Stats Score 9.9 to -2.6, ranking #266 overall.

In the 6 individual benchmarks reported for both models, Claude 3 Opus wins 6; this is a narrower head-to-head signal than the composite indexes.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude 3 Opus

  • overall performance matters — it scores 9.9 and ranks #266 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 6 of 6 exact shared results

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 Opus
Anthropic
Grok-1.5
xAI
Core performance indexes
LLM Stats Score
9.9
#266
-2.6
#339
Reasoning
9.8
#260
-2.2
#329
Coding
5.1
#201
-0.9
#245
Cost, coverage & limits
Benchmark wins
6 of 6
0 of 6
Input price
$15.00 / M
— / M
Output price
$75.00 / M
— / M
Context window
200,000
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

3 shared
Index
Claude 3 Opus
Grok-1.5
Math
16.1#210
4.9#277
Finance
14.3#129
4.7#174
Legal
14.3#112
4.7#158
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

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

6 shared

Claude 3 Opus outperforms in 6 benchmarks (GPQA, GSM8k, HumanEval, MATH, MMLU, MMLU-Pro), while Grok-1.5 is better at 0 benchmarks.

Claude 3 Opus significantly outperforms across most benchmarks.

Mon Sep 14 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 Opus specifies input context (200,000 tokens). Only Claude 3 Opus specifies output context (200,000 tokens).

Anthropic
Claude 3 Opus
Input200,000 tokens
Output200,000 tokens
xAI
Grok-1.5
Input- tokens
Output- tokens
Mon Sep 14 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

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

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

Claude 3 Opus

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 Opus

Proprietary

Closed source

Grok-1.5

Proprietary

Closed source

Release Timeline

When each model was launched

Claude 3 Opus 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 Opus.

Claude 3 Opus

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 Opus and Grok-1.5 side-by-side, then vote on the output you prefer.

Claude 3 Opus
✓ Preferred
Grok-1.5
Open in Playground

FAQ

Common questions about Claude 3 Opus vs Grok-1.5.

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

Claude 3 Opus leads the LLM Stats Score 9.9 to -2.6. Claude 3 Opus 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 Opus compare to Grok-1.5 in benchmarks?

Claude 3 Opus scores ARC-C: 96.4%, HellaSwag: 95.4%, GSM8k: 95.0%, MGSM: 90.7%, BIG-Bench Hard: 86.8%. 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 Opus and Grok-1.5?

Claude 3 Opus 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 Opus and Grok-1.5?

Key differences include LLM Stats Score (9.9 vs -2.6), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude 3 Opus and Grok-1.5?

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

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