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Claude Sonnet 5.5 vs Grok 4.7

Side-by-side pricing per provider, context window, benchmark scores and speed, all on one OpenAI-compatible API.

Metric
Claude Sonnet 5.5Anthropicanthropic/claude-sonnet-5.5
Grok 4.7xAIx-ai/grok-4.7
Creator
Anthropic
xAI
Released
Sep 28, 2026
Sep 21, 2026
Context window
1M (best)
500K
Max output
128K
500K (best)
Input / 1MLowest provider price
$2.00
$2.00
Output / 1MLowest provider price
$10.00
$6.00 (best)
Providers
1
1
IntelligenceArtificial Analysis index
56.0 (best)
46.3
Accepts
Text, Image
Text, Image
Produces
Text
Text
Tool calling
Yes
Yes
Structured output
Yes
Yes
Reasoning
Yes
No

Claude Sonnet 5.5 vs Grok 4.7: summary

Claude Sonnet 5.5 and Grok 4.7 are both available through FastRouter's OpenAI-compatible API, so switching between them is a change of model id, not a new integration.

Claude Sonnet 5.5, from Anthropic, has a 1,000,000-token context window, costs $2.00/1M input and $10.00/1M output tokens and scores 56.0 on the Artificial Analysis Intelligence Index.

Grok 4.7, from xAI, has a 500,000-token context window, costs $2.00/1M input and $6.00/1M output tokens and scores 46.3 on the Artificial Analysis Intelligence Index.

Claude Sonnet 5.5 has the largest context window and Claude Sonnet 5.5 scores highest for intelligence.

Switch with one line

client = OpenAI(base_url="https://api.fastrouter.ai/api/v1", api_key="<FASTROUTER_API_KEY>") client.chat.completions.create(model="anthropic/claude-sonnet-5.5", messages=[...]) # or client.chat.completions.create(model="x-ai/grok-4.7", messages=[...])
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Benchmark scores sourced from ArtificialAnalysis