Grok 4 Fast (reasoning) vs Claude 4.5 Sonnet (thinking)
Detailed comparison of capabilities, features, and performance.
Feature
Grok 4 Fast (reasoning)
Claude 4.5 Sonnet (thinking)
Model Image
AI Lab
xAI
Anthropic
Context Size
2,000,000 tokens
1,000,000 tokens
Max Output Size
30,000 tokens
64,000 tokens
Frontier Model
Yes
Yes
Vision Support
No
Yes
Description
Reasoning-enabled Grok 4 with 2m context. Low latency for time-sensitive tasks and huge context window.
The latest Claude 4.5 Sonnet model from Anthropic with maximum reasoning enabled, 200k reasoning tokens in 1M context.
Learn more about Grok 4 Fast (reasoning)
View detailed specifications and capabilities
View model details →Learn more about Claude 4.5 Sonnet (thinking)
View detailed specifications and capabilities
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