Gemini 3.1 Pro Preview Custom Tools vs GPT-6 Astra

Price, context window & benchmark comparison

Gemini 3.1 Pro Preview Custom Tools

Google

$2.00 / $12.00

Input / Output · per 1M tokens

GPT-6 Astra

OpenAI

$10.00 / $50.00

Input / Output · per 1M tokens

Compare different models

Verdict: Gemini 3.1 Pro Preview Custom Tools is 4.4× cheaper than GPT-6 Astra on a typical 3:1 input/output mix. GPT-6 Astra has the larger context window (1.1M vs 1M).

	Gemini 3.1 Pro Preview Custom Tools	GPT-6 Astra
Input price / 1M	$2.00	$10.00
Output price / 1M	$12.00	$50.00
Blended price (3:1)	$4.50	$20.00
Cached input / 1M	$0.20	$1.00
Context window	1M	1.1M
Max output	66K	128K
Intelligence index	—	52.7
Coding index	—	76.9
Providers	—	6
Best provider uptime (30m)	—	100.0%
Vision input	Yes	Yes
Reasoning	Yes	Yes
Tool calling	Yes	Yes
Released	2026-02-25	2026-09-04
Retirement	—	—

Cost calculator

Input tokens / requestOutput tokens / requestRequests / day

FAQ

Which is cheaper, Gemini 3.1 Pro Preview Custom Tools or GPT-6 Astra?

Gemini 3.1 Pro Preview Custom Tools is 4.4× cheaper than GPT-6 Astra on a typical 3:1 input/output mix.

Gemini 3.1 Pro Preview Custom Tools vs GPT-6 Astra: which has a bigger context window?

Gemini 3.1 Pro Preview Custom Tools: 1,048,576 tokens. GPT-6 Astra: 1,050,000 tokens.

How much would 1 million requests cost?

At 2,000 input + 500 output tokens per request: Gemini 3.1 Pro Preview Custom Tools ≈ $10,000, GPT-6 Astra ≈ $45,000.

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