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Gemini 3.1 Pro Preview vs GPT-5.5-Cyber

Gemini 3.1 Pro Preview (2026) and GPT-5.5-Cyber (2026) are frontier reasoning models from Google DeepMind and OpenAI. Gemini 3.1 Pro Preview ships a 1M-token context window, while GPT-5.5-Cyber ships a not-yet-sourced context window. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing. The goal is to make the tradeoff clear before deeper testing.

GPT-5.5-Cyber is safer overall; choose Gemini 3.1 Pro Preview when coding workflow support matters.

Decision scorecard

Local evidence first
SignalGemini 3.1 Pro PreviewGPT-5.5-Cyber
Decision fitCoding, RAG, and AgentsVision
Context window1M
Cheapest output$12/1M tokens-
Provider routes4 tracked0 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose Gemini 3.1 Pro Preview when...
  • Gemini 3.1 Pro Preview has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Gemini 3.1 Pro Preview has broader tracked provider coverage for fallback and procurement flexibility.
  • Gemini 3.1 Pro Preview uniquely exposes Function calling, Tool use, and Structured outputs in local model data.
  • Local decision data tags Gemini 3.1 Pro Preview for Coding, RAG, and Agents.
Choose GPT-5.5-Cyber when...
  • GPT-5.5-Cyber uniquely exposes Reasoning in local model data.
  • Local decision data tags GPT-5.5-Cyber for Vision.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output prices on this page.

Gemini 3.1 Pro Preview

$4,600

Cheapest tracked route: Google AI Studio

GPT-5.5-Cyber

Unavailable

No complete token price in local provider data

Cost delta unavailable until both models have sourced input and output token prices.

Switch friction

Gemini 3.1 Pro Preview -> GPT-5.5-Cyber
  • No overlapping tracked provider route is sourced for Gemini 3.1 Pro Preview and GPT-5.5-Cyber; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Function calling, Tool use, and Structured outputs before moving production traffic.
  • GPT-5.5-Cyber adds Reasoning in local capability data.
GPT-5.5-Cyber -> Gemini 3.1 Pro Preview
  • No overlapping tracked provider route is sourced for GPT-5.5-Cyber and Gemini 3.1 Pro Preview; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Reasoning before moving production traffic.
  • Gemini 3.1 Pro Preview adds Function calling, Tool use, and Structured outputs in local capability data.

Specs

Specification
Released2026-02-192026-04-30
Context window1M
Parameters
Architecturedecoder onlydecoder only
LicenseProprietaryProprietary
Knowledge cutoff2025-01-

Pricing and availability

Pricing attributeGemini 3.1 Pro PreviewGPT-5.5-Cyber
Input price$2/1M tokens-
Output price$12/1M tokens-
Providers-

Capabilities

CapabilityGemini 3.1 Pro PreviewGPT-5.5-Cyber
VisionYesYes
MultimodalYesYes
ReasoningNoYes
Function callingYesNo
Tool useYesNo
Structured outputsYesNo
Code executionYesNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on reasoning mode: GPT-5.5-Cyber, function calling: Gemini 3.1 Pro Preview, tool use: Gemini 3.1 Pro Preview, structured outputs: Gemini 3.1 Pro Preview, and code execution: Gemini 3.1 Pro Preview. Both models share vision and multimodal input, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

Pricing coverage is uneven: Gemini 3.1 Pro Preview has $2/1M input tokens and GPT-5.5-Cyber has no token price sourced yet. Provider availability is 4 tracked routes versus 0. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose Gemini 3.1 Pro Preview when coding workflow support and broader provider choice are central to the workload. Choose GPT-5.5-Cyber when reasoning depth are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.

FAQ

Is Gemini 3.1 Pro Preview or GPT-5.5-Cyber open source?

Gemini 3.1 Pro Preview is listed under Proprietary. GPT-5.5-Cyber is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Which is better for vision, Gemini 3.1 Pro Preview or GPT-5.5-Cyber?

Both Gemini 3.1 Pro Preview and GPT-5.5-Cyber expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, Gemini 3.1 Pro Preview or GPT-5.5-Cyber?

Both Gemini 3.1 Pro Preview and GPT-5.5-Cyber expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.

Which is better for reasoning mode, Gemini 3.1 Pro Preview or GPT-5.5-Cyber?

GPT-5.5-Cyber has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for function calling, Gemini 3.1 Pro Preview or GPT-5.5-Cyber?

Gemini 3.1 Pro Preview has the clearer documented function calling signal in this comparison. If function calling is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run Gemini 3.1 Pro Preview and GPT-5.5-Cyber?

Gemini 3.1 Pro Preview is available on Google AI Studio, GCP Vertex AI, OpenRouter, and Replicate API. GPT-5.5-Cyber is available on the tracked providers still being sourced. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-05-14. Data sourced from public model cards and provider documentation.