Gemini 3.1 Pro Preview 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 has held the same list price since 2026-08-15 and is the 99th cheapest of 108 Mid-tier models. None of its 2 hosts undercuts the price quoted here. 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): $1.00 / $6.00
- Prompt-cache read: $0.20
- Context window: 1M
- Arena ELO: 1487 (as of 2026-09-25)
- Available on: Direct API, Google Vertex, OpenRouter (curated by hand, verify with the provider)
Gemini 3.1 Pro Preview 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. Its Arena ELO of 1487 ranks 6th of the 68 models that carry one, above 93% of them.
Gemini 3.1 Pro Preview licence, size and capabilities
Gemini 3.1 Pro Preview 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 | $1.6K – $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 | $474 – $1.0K |
| Call Summary | 2,000 / 700 | $604 – $1.2K |
| Agent Workflow | 6,000 / 3,000 | $4.0K – $4.8K |
Gemini 3.1 Pro Preview 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 2 different hosts. 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.
The price we publish is already the cheapest of the 2 hosts: Google at $2.00 input / $12.00 output per 1M tokens. All of them charge within 10% of one another.
| Host | Input $/1M | Output $/1M |
|---|---|---|
| Google (the price shown above) | $2.00 | $12.00 |
| Google AI Studio (the price shown above) | $2.00 | $12.00 |
Gemini 3.1 Pro Preview price history
Gemini 3.1 Pro Preview 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
- 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.
The nearest Mid-tier models on Arena ELO, each with its blended price and score difference against Gemini 3.1 Pro Preview.
- Gemini 3.7 Flash (Google) — $0.75 in / $3.75 out per 1M, Arena ELO 1488: 68% cheaper, 1 ELO point higher
- Gemini 3.6 Flash (Google) — $0.75 in / $3.75 out per 1M, Arena ELO 1482: 68% cheaper, 5 ELO points lower
- GLM 5.3 (Zhipu) — $1.40 in / $4.40 out per 1M, Arena ELO 1480: 61% cheaper, 7 ELO points lower
- Gemini 3.5 Flash (Google) — $1.50 in / $9.00 out per 1M, Arena ELO 1477: 25% cheaper, 10 ELO points lower
- Cheapest within 15 Arena points: GLM 5.3 Flash (Zhipu), 96% cheaper, 13 ELO points lower, out of 17 models in that band.
- Highest Arena ELO within 20% of this price: Gemini 3.1 Pro Preview itself has the highest score of the 7 models priced within 20% of it.
Gemini 3.1 Pro Preview head to head
- Claude Opus 5 vs Gemini 3.1 Pro Preview
- GPT-5.5 vs Gemini 3.1 Pro Preview
- Gemini 3.1 Pro Preview vs Gemini 3.5 Flash
Common questions about Gemini 3.1 Pro Preview pricing
- How much does Gemini 3.1 Pro Preview cost?
- Gemini 3.1 Pro Preview costs $2.00 per million input tokens and $12.00 per million output tokens on the API.
- Does Gemini 3.1 Pro Preview offer batch or cached pricing?
- Yes. Batch API pricing is $1.00/M input and $6.00/M output. Prompt-cache reads cost $0.20/M.
- What would Gemini 3.1 Pro Preview 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 costs about $900 at list prices.
- Has the price of Gemini 3.1 Pro Preview changed?
- Gemini 3.1 Pro Preview 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 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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