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Claude Opus 4.1 vs Grok-4 Fast Non-Reasoning

Comparing Claude Opus 4.1 and Grok-4 Fast Non-Reasoning across benchmarks, pricing, and capabilities.

Anthropic · xAI · Updated for 2026

Which is better?

Claude Opus 4.1 and Grok-4 Fast Non-Reasoning trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

On price, Grok-4 Fast Non-Reasoning is roughly 109.1x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Grok-4 Fast Non-Reasoning also accepts a larger context window (2,000,000 input tokens), making it the stronger choice for long documents and large codebases.

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

Choose Claude Opus 4.1

  • you want predictable pricing at $15.00/M input and $75.00/M output

Choose Grok-4 Fast Non-Reasoning

  • cost matters — it's about 109.1x cheaper per token
  • you process long inputs — it offers a 2,000,000 token context window
  • you want the most recent training data — it shipped Aug 2025

At a glance

The differences that matter most.

Benchmark wins
Input price
$15.00 / M
$0.20 / M
Output price
$75.00 / M
$0.50 / M
Context window
200,000
2,000,000
Released
Aug 2025
Aug 2025
License
Proprietary
Proprietary

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

Claude Opus 4.1 and Grok-4 Fast Non-Reasoningdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Playground indexes and blind preference scores

Pricing Analysis

Price comparison per million tokens

Grok-4 Fast Non-Reasoning costs less

For input processing, Claude Opus 4.1 ($15.00/1M tokens) is 75.0x more expensive than Grok-4 Fast Non-Reasoning ($0.20/1M tokens).

For output processing, Claude Opus 4.1 ($75.00/1M tokens) is 150.0x more expensive than Grok-4 Fast Non-Reasoning ($0.50/1M tokens).

In conclusion, Claude Opus 4.1 is more expensive than Grok-4 Fast Non-Reasoning.*

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

Lowest available price from all providers
Tue Aug 25 2026 • llm-stats.com
Anthropic
Claude Opus 4.1
Input tokens$15.00
Output tokens$75.00
Best providerAnthropic
xAI
Grok-4 Fast Non-Reasoning
Input tokens$0.20
Output tokens$0.50
Best providerxAI
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

Grok-4 Fast Non-Reasoning accepts 2,000,000 input tokens compared to Claude Opus 4.1's 200,000 tokens. Claude Opus 4.1 can generate longer responses up to 32,000 tokens, while Grok-4 Fast Non-Reasoning is limited to 30,000 tokens.

Anthropic
Claude Opus 4.1
Input200,000 tokens
Output32,000 tokens
xAI
Grok-4 Fast Non-Reasoning
Input2,000,000 tokens
Output30,000 tokens
Tue Aug 25 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Opus 4.1 and Grok-4 Fast Non-Reasoning support multimodal inputs.

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

Claude Opus 4.1

Text
Images
Audio
Video

Grok-4 Fast Non-Reasoning

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 Opus 4.1

Proprietary

Closed source

Grok-4 Fast Non-Reasoning

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 4.1 was released on 2025-08-05, while Grok-4 Fast Non-Reasoning was released on 2025-08-28.

Grok-4 Fast Non-Reasoning is 1 month newer than Claude Opus 4.1.

Claude Opus 4.1

Aug 5, 2025

1.1 years ago

Grok-4 Fast Non-Reasoning

Aug 28, 2025

12 months ago

3w 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

Provider Availability

Claude Opus 4.1 is available from Anthropic, Bedrock, Google. Grok-4 Fast Non-Reasoning is available from xAI.

Claude Opus 4.1

anthropic logo
Anthropic
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M
bedrock logo
AWS Bedrock
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M
google logo
Google
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M

Grok-4 Fast Non-Reasoning

xai logo
xAI
Input Price:Input: $0.20/1MOutput Price:Output: $0.50/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Claude Opus 4.1 and Grok-4 Fast Non-Reasoning side-by-side, then vote on the output you prefer.

Claude Opus 4.1
✓ Preferred
Grok-4 Fast Non-Reasoning
Open in Playground

FAQ

Common questions about Claude Opus 4.1 vs Grok-4 Fast Non-Reasoning.

Which is better, Claude Opus 4.1 or Grok-4 Fast Non-Reasoning?

Claude Opus 4.1 (Anthropic) and Grok-4 Fast Non-Reasoning (xAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does Claude Opus 4.1 compare to Grok-4 Fast Non-Reasoning in benchmarks?

Claude Opus 4.1 scores MMMLU: 89.5%, TAU-bench Retail: 82.4%, GPQA: 80.9%, AIME 2025: 78.0%, MMMU (validation): 77.1%.

Is Claude Opus 4.1 cheaper than Grok-4 Fast Non-Reasoning?

Grok-4 Fast Non-Reasoning is 75.0x cheaper for input tokens. Claude Opus 4.1 costs $15.00/M input and $75.00/M output via anthropic. Grok-4 Fast Non-Reasoning costs $0.20/M input and $0.50/M output via xai.

What are the context window sizes for Claude Opus 4.1 and Grok-4 Fast Non-Reasoning?

Claude Opus 4.1 supports 200K tokens and Grok-4 Fast Non-Reasoning supports 2.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Opus 4.1 and Grok-4 Fast Non-Reasoning?

Key differences include context window (200K vs 2.0M), input pricing ($15.00 vs $0.20/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 4.1 and Grok-4 Fast Non-Reasoning?

Claude Opus 4.1 is developed by Anthropic and Grok-4 Fast Non-Reasoning is developed by xAI.