Gemini 3.1 Pro Preview Custom Tools API Pricing
Google · Mid-tier · Proprietary · released 2026-02. Prices in USD per 1 million tokens. Data snapshot: 2026-09-28.
Gemini 3.1 Pro Preview Custom Tools has held the same list price since 2026-08-15 and is the 99th cheapest of 108 Mid-tier models. Only one host, Google AI Studio, sells it, so there is no second price to shop. Its name marks it as a preview, beta or experimental release, so both the model and its price are provisional.
- Input: $2.00 per 1M tokens
- Output: $12.00 per 1M tokens
- Batch API (input/output): not published
- Prompt-cache read: $0.20
- Context window: 1M
Gemini 3.1 Pro Preview Custom Tools market position
On blended price ($9.00 per 1M tokens at 30% input, 70% output) it is cheaper than 6% of Mid-tier models: 99th cheapest of 108, tied with 3 others. Across every category it is cheaper than 13% of priced text models in the catalogue: 241st cheapest of 281, tied with 3 others.
Gemini 3.1 Pro Preview Custom Tools licence, size and capabilities
Gemini 3.1 Pro Preview Custom Tools is recorded here as proprietary: access is through an API, priced by the token. Its parameter count is not published. Listed capabilities: Text, Vision, Audio, Reasoning, Code, Agents. Filling its 1M context window once costs $2.00 in input tokens at list price.
Monthly cost at 100K requests, by business use case
From the after-discounts figure (prompt caching on the cached input share, batch API for async workloads, only where the provider publishes those rates), which assumes you implement both, to the list price. One figure means no discount is published.
| Use case | Tokens (in/out) | Monthly (after discounts – list) |
|---|---|---|
| Support Ticket | 1,500 / 500 | $738 – $900 |
| Knowledge Q&A | 2,000 / 800 | $1.1K – $1.4K |
| Meeting Summary | 10,000 / 1,200 | $3.3K – $3.4K |
| Marketing Content | 2,500 / 1,800 | $2.6K – $2.7K |
| Coding Task | 3,000 / 2,000 | $2.7K – $3.0K |
| Invoice Processing | 1,500 / 600 | $939 – $1.0K |
| Call Summary | 2,000 / 700 | $1.2K |
| Agent Workflow | 6,000 / 3,000 | $4.0K – $4.8K |
Gemini 3.1 Pro Preview Custom Tools pricing by host
A host is a company that runs the model and sells it by the token — the lab that made it, a cloud platform like Amazon Bedrock, Azure or Vertex, or an independent provider. One model, several sellers, and often several prices. This model is sold by 1 host. The price quoted above is the one we publish so that models stay comparable; it is not necessarily the cheapest way to buy this model. List prices as published on 2026-09-28 via OpenRouter — negotiated rates, committed-use discounts and provisioned capacity are not shown.
Google AI Studio is the only host with a published rate, $2.00 input / $12.00 output per 1M tokens, which is the price shown on this page.
| Host | Input $/1M | Output $/1M |
|---|---|---|
| Google AI Studio (the price shown above) | $2.00 | $12.00 |
Gemini 3.1 Pro Preview Custom Tools price history
Gemini 3.1 Pro Preview Custom Tools has been in our daily price archive since tracking began on 2026-08-15, when it listed at $2.00 input / $12.00 output per 1M tokens. No list price change since tracking began on 2026-08-15. Last checked against the 2026-09-28 snapshot.
Alternatives to Gemini 3.1 Pro Preview Custom Tools
- Next cheaper Mid-tier model: Command A (Cohere) at $7.75 blended, 14% less.
- Next more expensive: Nova Premier 1.0 (Amazon) at $9.50 blended, 6% more.
Common questions about Gemini 3.1 Pro Preview Custom Tools pricing
- How much does Gemini 3.1 Pro Preview Custom Tools cost?
- Gemini 3.1 Pro Preview Custom Tools costs $2.00 per million input tokens and $12.00 per million output tokens on the API.
- Does Gemini 3.1 Pro Preview Custom Tools offer batch or cached pricing?
- Prompt-cache reads cost $0.20/M input tokens. No batch pricing is published.
- What would Gemini 3.1 Pro Preview Custom Tools cost per month?
- For a support-ticket workload (1,500 input + 500 output tokens per request) at 100K requests/month, Gemini 3.1 Pro Preview Custom Tools costs about $900 at list prices.
- Has the price of Gemini 3.1 Pro Preview Custom Tools changed?
- Gemini 3.1 Pro Preview Custom Tools has been in our daily price archive since tracking began on 2026-08-15, when it listed at $2.00 input / $12.00 output per 1M tokens. No list price change since tracking began on 2026-08-15. Last checked against the 2026-09-28 snapshot.
These are list prices: real cost also depends on caching, batching, negotiated discounts, marketplace agreements, and existing contracts. Get a FinOps review from OptimNow or compare all models.
Build the business case for Gemini 3.1 Pro Preview Custom Tools in the AI ROI Calculator: add your business value on top of these costs to get ROI, break-even and payback.
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