LLM Reference

Gemini 3.1 Pro Preview vs GPT-4o-mini Search Preview

Gemini 3.1 Pro Preview (2026) and GPT-4o-mini Search Preview (2025) are compact production models from Google DeepMind and OpenAI. Gemini 3.1 Pro Preview ships a 1M-token context window, while GPT-4o-mini Search Preview ships a 128K-token context window. On pricing, GPT-4o-mini Search Preview costs $0.15/1M input tokens versus $2/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.

GPT-4o-mini Search Preview is ~1233% cheaper at $0.15/1M; pay for Gemini 3.1 Pro Preview only for coding workflow support.

Decision scorecard

Local evidence first
SignalGemini 3.1 Pro PreviewGPT-4o-mini Search Preview
Decision fitCoding, RAG, and AgentsRAG, Long context, and Classification
Context window1M128K
Cheapest output$12/1M tokens$0.6/1M tokens
Provider routes4 tracked1 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 Vision, Multimodal, and Function calling in local model data.
  • Local decision data tags Gemini 3.1 Pro Preview for Coding, RAG, and Agents.
Choose GPT-4o-mini Search Preview when...
  • GPT-4o-mini Search Preview has the lower cheapest tracked output price at $0.6/1M tokens.
  • Local decision data tags GPT-4o-mini Search Preview for RAG, Long context, and Classification.

Monthly cost at traffic

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

Lower estimate GPT-4o-mini Search Preview

Gemini 3.1 Pro Preview

$4,600

Cheapest tracked route: Google AI Studio

GPT-4o-mini Search Preview

$270

Cheapest tracked route: OpenRouter

Estimated monthly gap: $4,330. Batch, cache, and negotiated pricing are excluded from this local estimate.

Switch friction

Gemini 3.1 Pro Preview -> GPT-4o-mini Search Preview
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • GPT-4o-mini Search Preview is $11.40/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Vision, Multimodal, and Function calling before moving production traffic.
GPT-4o-mini Search Preview -> Gemini 3.1 Pro Preview
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Gemini 3.1 Pro Preview is $11.40/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Gemini 3.1 Pro Preview adds Vision, Multimodal, and Function calling in local capability data.

Specs

Specification
Released2026-02-192025-02-26
Context window1M128K
Parameters
Architecturedecoder onlydecoder only
LicenseProprietaryUnknown
Knowledge cutoff2025-012023-10

Pricing and availability

Pricing attributeGemini 3.1 Pro PreviewGPT-4o-mini Search Preview
Input price$2/1M tokens$0.15/1M tokens
Output price$12/1M tokens$0.6/1M tokens
Providers

Capabilities

CapabilityGemini 3.1 Pro PreviewGPT-4o-mini Search Preview
VisionYesNo
MultimodalYesNo
ReasoningNoNo
Function callingYesNo
Tool useYesNo
Structured outputsYesYes
Code executionYesNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on vision: Gemini 3.1 Pro Preview, multimodal input: Gemini 3.1 Pro Preview, function calling: Gemini 3.1 Pro Preview, tool use: Gemini 3.1 Pro Preview, and code execution: Gemini 3.1 Pro Preview. Both models share structured outputs, 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.

For cost, Gemini 3.1 Pro Preview lists $2/1M input and $12/1M output tokens, while GPT-4o-mini Search Preview lists $0.15/1M input and $0.6/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts GPT-4o-mini Search Preview lower by about $4.71 per million blended tokens. Availability is 4 providers versus 1, so concentration risk also matters.

Choose Gemini 3.1 Pro Preview when coding workflow support, larger context windows, and broader provider choice are central to the workload. Choose GPT-4o-mini Search Preview when provider fit and lower input-token cost are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.

FAQ

Which has a larger context window, Gemini 3.1 Pro Preview or GPT-4o-mini Search Preview?

Gemini 3.1 Pro Preview supports 1M tokens, while GPT-4o-mini Search Preview supports 128K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Which is cheaper, Gemini 3.1 Pro Preview or GPT-4o-mini Search Preview?

GPT-4o-mini Search Preview is cheaper on tracked token pricing. Gemini 3.1 Pro Preview costs $2/1M input and $12/1M output tokens. GPT-4o-mini Search Preview costs $0.15/1M input and $0.6/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is Gemini 3.1 Pro Preview or GPT-4o-mini Search Preview open source?

Gemini 3.1 Pro Preview is listed under Proprietary. GPT-4o-mini Search Preview is listed under Unknown. 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-4o-mini Search Preview?

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

Which is better for multimodal input, Gemini 3.1 Pro Preview or GPT-4o-mini Search Preview?

Gemini 3.1 Pro Preview has the clearer documented multimodal input signal in this comparison. If multimodal input 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-4o-mini Search Preview?

Gemini 3.1 Pro Preview is available on Google AI Studio, GCP Vertex AI, OpenRouter, and Replicate API. GPT-4o-mini Search Preview is available on OpenRouter. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-05-11. Data sourced from public model cards and provider documentation.