Which is cheaper, GPT-6 Astra and Grok 4.6?

Grok 4.6 has the lowest input price. Per 1M input tokens: GPT-6 Astra from $10.00 and Grok 4.6 from $2.00.

Which has the larger context window, GPT-6 Astra and Grok 4.6?

GPT-6 Astra has the largest context window: GPT-6 Astra 1,050,000 tokens and Grok 4.6 500,000 tokens.

Which is better for coding, GPT-6 Astra and Grok 4.6?

GPT-6 Astra scores highest on the Artificial Analysis Coding Index: GPT-6 Astra 77.1 and Grok 4.6 76.8.

Can I switch between GPT-6 Astra and Grok 4.6 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 (openai/gpt-6-astra, x-ai/grok-4.6).

GPT-6 Astra vs Grok 4.6

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

GPT-6 Astra OpenAIopenai/gpt-6-astra

Grok 4.6 xAIx-ai/grok-4.6

Creator

OpenAI

xAI

Released

Sep 4, 2026

Aug 12, 2026

Context window

1.05M

500K

Max output

128K

500K

Input / 1MLowest provider price

$10.00

$2.00

Output / 1MLowest provider price

$50.00

$6.00

Providers

IntelligenceArtificial Analysis index

50.9

44.3

CodingArtificial Analysis index

77.1

76.8

Accepts

Text, Image

Produces

Text

Tool calling

Yes

Structured output

Yes

Reasoning

Yes

GPT-6 Astra vs Grok 4.6: summary

GPT-6 Astra and Grok 4.6 are both available through FastRouter's OpenAI-compatible API, so switching between them is a change of model id, not a new integration.

GPT-6 Astra, from OpenAI, has a 1,050,000-token context window, costs $10.00/1M input and $50.00/1M output tokens and scores 50.9 on the Artificial Analysis Intelligence Index.

Grok 4.6, from xAI, has a 500,000-token context window, costs $2.00/1M input and $6.00/1M output tokens and scores 44.3 on the Artificial Analysis Intelligence Index.

Grok 4.6 is the cheapest on input, 5× cheaper than the next model, GPT-6 Astra has the largest context window, GPT-6 Astra scores highest for intelligence and GPT-6 Astra leads on coding.

Switch with one line

client = OpenAI(base_url="https://api.fastrouter.ai/api/v1", api_key="<FASTROUTER_API_KEY>") client.chat.completions.create(model="openai/gpt-6-astra", messages=[...]) # or client.chat.completions.create(model="x-ai/grok-4.6", messages=[...])

Full API docs

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Benchmark scores sourced from ArtificialAnalysis