Gemini 3.1 Pro Cost Calculator

Google's flagship reasoning model. $2 input / $12 output per 1M tokens with a 2M-token context window.

Gemini 3.1 Pro is Google's flagship reasoning model with the largest context window on the market — 2 million tokens at base pricing. At $2/$12 per million it is priced head-to-head with GPT-5.4.

Above 200K context, pricing tiers to $4 input / $18 output. Use this calculator to model both short and long-context scenarios, and compare against Claude Opus 4.7 ($5/$25) and GPT-5.5 ($5/$30).

Models included

GPT-5.5 (OpenAI) — $5.00 input / $30.00 output per 1M tokens · 1M context window
Claude Opus 4.7 (Anthropic) — $5.00 input / $25.00 output per 1M tokens · 1M context window
Gemini 3.1 Pro (Google) — $2.00 input / $12.00 output per 1M tokens · 2M context window

Frequently asked questions

How much does Gemini 3.1 Pro cost?

Gemini 3.1 Pro costs $2 per million input tokens and $12 per million output tokens up to 200K context. Above 200K, pricing tiers to $4 input / $18 output. Cached input is $0.20 per 1M.

Is Gemini 3.1 Pro free?

No. As of April 1, 2026, Google removed Gemini Pro models from the free tier — Gemini 3.1 Pro is paid-only. Flash models (3 Flash, 3.1 Flash-Lite) retain a reduced free tier.

What is the Gemini 3.1 Pro context window?

2 million tokens — the largest context window of any frontier model in 2026.

Should I use 3.1 Pro or 3.5 Flash?

Use Flash for most workloads (faster, 25% cheaper, near-frontier quality). Reach for 3.1 Pro when you need genuinely deep reasoning or a 2M-token context window.