Which is cheaper, Claude Opus 5.5 and Grok 4.7?

Grok 4.7 has the lowest input price. Per 1M input tokens: Claude Opus 5.5 from $4.00 and Grok 4.7 from $2.00.

Which has the larger context window, Claude Opus 5.5 and Grok 4.7?

Claude Opus 5.5 has the largest context window: Claude Opus 5.5 1,000,000 tokens and Grok 4.7 500,000 tokens.

Which is smarter, Claude Opus 5.5 and Grok 4.7?

Claude Opus 5.5 scores highest on the Artificial Analysis Intelligence Index: Claude Opus 5.5 57.6 and Grok 4.7 46.3.

Can I switch between Claude Opus 5.5 and Grok 4.7 without changing my code?

Yes. All of them are served through FastRouter's OpenAI-compatible API, so switching is a change of the model parameter (anthropic/claude-opus-5.5, x-ai/grok-4.7).

Claude Opus 5.5 vs Grok 4.7

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

Claude Opus 5.5 Anthropicanthropic/claude-opus-5.5

Grok 4.7 xAIx-ai/grok-4.7

Creator

Anthropic

xAI

Released

Sep 22, 2026

Sep 21, 2026

Context window

500K

Max output

128K

500K

Input / 1MLowest provider price

$4.00

$2.00

Output / 1MLowest provider price

$20.00

$6.00

Providers

IntelligenceArtificial Analysis index

57.6

46.3

Accepts

Text, Image, Files

Text, Image

Produces

Text

Tool calling

Yes

Structured output

Yes

Reasoning

Yes

Claude Opus 5.5 vs Grok 4.7: summary

Claude Opus 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 Opus 5.5, from Anthropic, has a 1,000,000-token context window, costs $4.00/1M input and $20.00/1M output tokens and scores 57.6 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.

Grok 4.7 is the cheapest on input, 2× cheaper than the next model, Claude Opus 5.5 has the largest context window and Claude Opus 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-opus-5.5", messages=[...]) # or client.chat.completions.create(model="x-ai/grok-4.7", messages=[...])

Full API docs

Frequently asked questions

More comparisons

Benchmark scores sourced from ArtificialAnalysis