MODEL PROOF
Gemini 3.1 Pro Preview
BETTER VALUE OPTION
A stored alternative has an equal-or-higher measured score and an equal-or-lower price.
Base context tier shown; inspect the complete context ladder below. · Reasoning tokens are billed separately.
Gemini 3.8 Flash · Δ score 14.6 points · 67% lower measured price · $1.50 / 1M tokens
- Independent LMArena score
- 1,480.1 ± 3.14 · 106,951 votes
- Context window
- 1.05M
- Maximum output
- 65.54K
- Input modalities
- audio, file, image, text, video
- Output modalities
- text
- Published input price
- $2.00 / 1M tokens
- Published output price
- $12.00 / 1M tokens
- Pricing kind
- fixed
- Context tiers
- Tiered by context
Inspect complete billing conditions and endpoint terms below.
Every price dimension · USD per million tokens
| Input | $2.00/M |
|---|---|
| Output | $12.00/M |
| Cached input | $0.200/M |
| Cache write | $0.375/M |
| Cache write 1h | Unknown/M |
| Reasoning | $12.00/M |
| Web search | $0.014/call |
| Batch discount | 50% |
The headline rate does not apply to a long-context workload.
Complete context ladder · 1 tier
| More than 200,000 tokens | $4.00/M in (2×) $18.00/M out $0.400/M cached input $0.375/M cache write |
|---|
Reasoning tokens are billed separately at $12.00/M, on top of output. Its share of your bill depends on the reasoning tokens used.
Who sells it
The same weights, different shops. Cheapest is not like-for-like when serving precision differs.
6 provider offers · rates, limits and conditions
Rates are USD per million tokens. Endpoint terms can differ even when the quoted price and precision match. A listed parameter is a provider declaration, not a task-success test.
| Seller | Input | Output | Precision | Uptime (1d) |
|---|---|---|---|---|
| Googlegoogle-vertex/global/flex Endpoint terms
| $1.00 | $6.00 | undeclared | 98.30% |
| Google AI Studiogoogle-ai-studio/flex Endpoint terms
| $1.00 | $6.00 | undeclared | 99.99% |
| Googlegoogle-vertex/global Endpoint terms
| $2.00 | $12.00 | undeclared | 98.58% |
| Google AI Studiogoogle-ai-studio Endpoint terms
| $2.00 | $12.00 | undeclared | 99.87% |
| Googlegoogle-vertex/global/priority Endpoint terms
| $3.60 | $21.60 | undeclared | 100.00% |
| Google AI Studiogoogle-ai-studio/priority Endpoint terms
| $3.60 | $21.60 | undeclared | 99.34% |
Independent scores
| LMArena Elo | 1480.1default |
|---|
LMArena Elo under CC BY 4.0. Absence of another board is not a score of zero.
Best rankings by task
- agentichtmlslides #4of 9 1226
- agenticslides(html) #4of 9 1219
- godotgamedev #5of 30 1236
- agenticslides #7of 9 1112
- agenticslides(python-pptx) #7of 9 1107
- pptxslides #7of 8 1110
- svg #9of 76 1305
- asciiart #9of 61 1285
Capability
| Context window | 1M |
|---|---|
| Max output | 66K |
| Input modes | audio, file, image, text, video |
| Tool use | yes |
| Reasoning | always on |
| Open weights | no |
Provenance
| Price source | openrouter.ai |
|---|---|
| Fetched | 2026-09-23 |
| Quality data | verified |
| Cross-checked | vendor page |
This is Gemini 3.1 Pro Preview, a published API row. It is not Gemini 3.5 Pro, which is not in this catalogue.
Our take
editorial — not a measurementThis preview-labelled Gemini accepts several input modalities in the recorded endpoint. For long documents, select the prompt size before comparing prices because the accepted table has a context threshold. Check the vendor’s storage terms as well as cache-read rates when holding context caches. Read the current benchmark evidence with its task and effort settings.
Strengths
- Audio, video, image, file and text input are listed
- The accepted table records context-tier and batch pricing
Weaknesses
- Cache storage and cache reads can be separate billing dimensions
- The preview label requires an availability and lifecycle check for production use
Reach for it when
- Multimodal task evaluations
- Document workflows with explicit cache-retention assumptions
Avoid it if
- You require a generally available rather than preview-labelled model
- Your estimate ignores prompt length or cache storage
Sources: ai.google.dev
Gemini 3.1 Pro Preview is Google’s frontier reasoning model, delivering enhanced software engineering performance, improved agentic reliability, and more efficient token usage across complex workflows. Building on the multimodal foundation...
Questions this page answers
What does Gemini 3.1 Pro Preview cost?
$2.00/M in, $12.00/M out in this catalogue, as of the fetch date on this page. That is the API row, not a subscription.
Does Gemini 3.1 Pro Preview have an independent quality score?
Gemini 3.1 Pro Preview has an LMArena score in this catalogue.
What beats Gemini 3.1 Pro Preview?
Gemini 3.8 Flash has an equal-or-higher measured score and an equal-or-lower price.
Does this page use Artificial Analysis scores for Gemini 3.1 Pro Preview?
No. Artificial Analysis figures are not published here. Quality on this page is LMArena Elo where a score exists; otherwise the row is unrated.
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[](https://undominated.ai/models/google__gemini-3.1-pro-preview/)<a href="https://undominated.ai/models/google__gemini-3.1-pro-preview/"><img src="https://undominated.ai/badge/google__gemini-3.1-pro-preview.svg" alt="Gemini 3.1 Pro Preview — Undominated.ai dominance verdict" height="36"></a>Direct file: https://undominated.ai/badge/google__gemini-3.1-pro-preview.svg — a static SVG, written by scripts/build-badges.mjs on every build, so the copy you embed is never
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