GooglereasoningGemini 3.1 Pro Preview pricing
$2.00 per 1M input tokens and $12.00 per 1M output tokens. In real work that is 2.1¢ per chat answer and 4.6¢ to summarize a 20-page PDF.
Official price at Google (Gemini API): $2.00 / $12.00 per 1M, cached $0.20 (source, verified Oct 18, 2026).
What Gemini 3.1 Pro Preview costs per task
Every row below was measured: we ran the task on this model and counted the tokens. Reasoning tokens are billed as output.
| Task | Cost | Tokens used | Price rank | Basis |
|---|---|---|---|---|
| Answer a chat question | 2.1¢$21.39 / 1,000 | 35 in · 915 out · 862 reasoning | 309 of 336 | measured |
| Reply to a customer email | 0.97¢$9.72 / 1,000 | 271 in · 128 out · 637 reasoning | 305 of 336 | measured |
| Write a 1,500-word blog post | 5.0¢$49.64 / 1,000 | 52 in · 2,522 out · 1,606 reasoning | 297 of 336 | measured |
| Write 10 product descriptions | 3.9¢$39.14 / 1,000 | 293 in · 1,229 out · 1,984 reasoning | 299 of 336 | measured |
| Translate 1,000 words | 11¢$109 / 1,000 | 1,308 in · 1,332 out · 7,494 reasoning | 319 of 336 | measured |
| Proofread one page (500 words) | 3.6¢$35.78 / 1,000 | 706 in · 653 out · 2,211 reasoning | 316 of 336 | measured |
| Summarize a 20-page PDF | 4.6¢$45.76 / 1,000 | 12,741 in · 611 out · 1,079 reasoning | 299 of 336 | measured |
| Extract data from an invoice | 3.2¢$31.94 / 1,000 | 452 in · 533 out · 2,053 reasoning | 319 of 336 | measured |
| Analyze a 200-row spreadsheet | 7.5¢$75.49 / 1,000 | 6,304 in · 882 out · 4,358 reasoning | 265 of 336 | measured |
| Answer from 5 retrieved documents (RAG) | 3.3¢$33.35 / 1,000 | 3,608 in · 599 out · 1,579 reasoning | 306 of 336 | measured |
| Classify 100 support tickets | 9.4¢$94.32 / 1,000 | 1,397 in · 565 out · 7,062 reasoning | 325 of 336 | measured |
| Review 500 lines of code | 11¢$114 / 1,000 | 5,207 in · 1,368 out · 7,256 reasoning | 295 of 336 | measured |
| Write a SQL query | 3.2¢$31.51 / 1,000 | 135 in · 620 out · 1,983 reasoning | 315 of 336 | measured |
| Run a 50-step coding agent | $1.95$1,949 / 1,000 | 2,194,987 in · 14,715 out · 99,150 reasoning | 286 of 336 | modeled |
Price at every provider
List prices per 1M tokens (input / output) at each host serving Gemini 3.1 Pro Preview through OpenRouter today. Hosts can differ in quantization, context and speed.
| Provider | Input / output | Cached input | Context | Uptime |
|---|---|---|---|---|
Googleunknown | $1.00 / $6.00 | $0.10 | 1M | |
Google AI Studiounknown | $1.00 / $6.00 | $0.10 | 1M | 100% |
Googleunknown | $2.00 / $12.00 | $0.20 | 1M | 100% |
Google AI Studiounknown | $2.00 / $12.00 | $0.20 | 1M | 100% |
Googleunknown | $3.60 / $21.60 | $0.36 | 1M | |
Google AI Studiounknown | $3.60 / $21.60 | $0.36 | 1M |
Price history
First seen in our price history on Mar 3, 2026 at $2.00 input / $12.00 output. The list price has not changed since.
FAQ
How much does Gemini 3.1 Pro Preview cost?
Gemini 3.1 Pro Preview costs $2.00 per 1 million input tokens and $12.00 per 1 million output tokens, with cached input at $0.20 (list price on Oct 18, 2026). In practice one chat answer costs about 2.1¢ and summarizing a 20-page PDF about 4.6¢.
Where is Gemini 3.1 Pro Preview cheapest?
Among 6 providers we track, the lowest list price today is at Google: $1.00 input and $6.00 output per 1M tokens.
Does Gemini 3.1 Pro Preview charge for reasoning tokens?
Yes. Reasoning (thinking) tokens are billed as output tokens. That is why the cost per task can be much higher than the visible answer suggests - our task costs include them.
Is the Gemini 3.1 Pro Preview cost per task measured or estimated?
Measured: we ran all 13 benchmark prompts on Gemini 3.1 Pro Preview through OpenRouter and recorded the tokens it used.