Anthropic: Claude Sonnet 4.5 vs xAI: Grok 4
Side-by-side comparison of Anthropic: Claude Sonnet 4.5 and xAI: Grok 4. Compare pricing, context window, capabilities, and find out which is better for your workflow.
Verdict
strong confidenceAnthropic: Claude Sonnet 4.5 leads overall
Anthropic: Claude Sonnet 4.5 leads in context window and max output, making it the stronger choice for most workflows. xAI: Grok 4 remains a solid alternative depending on your specific needs.
Best for with Anthropic: Claude Sonnet 4.5
Best for with xAI: Grok 4
Side-by-side
Technical specifications
| Anthropic: Claude Sonnet 4.5 | xAI: Grok 4 | |
|---|---|---|
| Provider | Anthropic | xAI |
| Input price | $3/M | $3/M |
| Output price | $15/M | $15/M |
| Context window | 1.0M | 256K |
| Max output | 64K | N/A |
| Capabilities | Tool useVisionReasoning | Tool useVisionReasoning |
| Released | Sep 29, 2025 | Jul 9, 2025 |
Scoring breakdown
How each dimension compares
Price
Anthropic: Claude Sonnet 4.5
$15/M tokens
xAI: Grok 4
$15/M tokens
Context Window
Anthropic: Claude Sonnet 4.5 leadsAnthropic: Claude Sonnet 4.5
1.0M tokens
xAI: Grok 4
256K tokens
Capabilities
Anthropic: Claude Sonnet 4.5
3/4
xAI: Grok 4
3/4
Max Output
Anthropic: Claude Sonnet 4.5 leadsAnthropic: Claude Sonnet 4.5
64K tokens
xAI: Grok 4
N/A
Recency
Anthropic: Claude Sonnet 4.5
Sep 2025
xAI: Grok 4
Jul 2025
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