---
title: "Gemini 3.1 Pro Preview — API access"
description: "Gemini 3.1 Pro Preview API pricing: official $2/$12 per 1M tokens, $1/$6 with the flat 50% apiToken.sale discount. Pro-tier reasoning on the native Google API."
url: "https://apitoken.sale/models/gemini-3-1-pro-preview"
language: "en"
---
# Gemini 3.1 Pro Preview

Gemini 3.1 Pro Preview is Google's Pro-tier reasoning model — the strongest Gemini for hard reasoning and long-horizon agentic work, with long-context rates above 200K input tokens.

- **Model ID:** `gemini-3.1-pro-preview`
- **Tier:** Pro
- **Context window:** 1M tokens
- **Max output:** 64K tokens
- **Official price (per 1M):** $2 input / $12 output
- **Your price (per 1M):** input $1, output $6 (flat 50% off)
- **Base URL:** `https://gemini.api.apitoken.sale` · **Endpoint:** `POST /v1beta/models/gemini-3.1-pro-preview:generateContent` (x-goog-api-key)

## Best for

- The hardest reasoning, planning and review work.
- Long-horizon agentic tasks with tool use.
- Deep document and codebase analysis in the 1M-token window.

## Notes

- Requests above 200K input tokens bill at long-context rates — $4/$18 per 1M (2× input, 1.5× output) on the whole request.
- Cached input bills at 10% of input; caching is automatic on repeated prefixes.

## Call it

```bash
curl https://gemini.api.apitoken.sale/v1beta/models/gemini-3.1-pro-preview:generateContent \
  -H "x-goog-api-key: $APITOKEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"contents": [{"parts": [{"text": "Reply with exactly: connected"}]}]}'
```

## FAQ

**How much does the Gemini 3.1 Pro Preview API cost?**

Officially $2 per 1M input tokens and $12 per 1M output tokens, with cached input at $0.20; above 200K input tokens the whole request bills at $4/$18. On apiToken.sale the flat 50% discount applies to every call — $1/$6, or $2/$9 at long-context rates.

**What is the model ID for Gemini 3.1 Pro Preview?**

gemini-3.1-pro-preview. Use it unchanged with the Google GenAI SDK or any Gemini-compatible tool pointed at https://gemini.api.apitoken.sale, with the key sent as x-goog-api-key.

**Gemini 3.1 Pro Preview or 3.6 Flash?**

3.6 Flash covers most workloads at a lower token price; route the hardest reasoning and longest-horizon runs to 3.1 Pro Preview. Both run on the same key, balance and endpoint.

---
API reference: https://apitoken.sale/md/docs · All models: https://apitoken.sale/md/models