LLM Reference

Gemini 2.5 Pro vs GPT-4o Search Preview

Gemini 2.5 Pro (2025) and GPT-4o Search Preview (2025) are frontier reasoning models from Google DeepMind and OpenAI. Gemini 2.5 Pro ships a 1m-token context window, while GPT-4o Search Preview ships a 128k-token context window. On pricing, Gemini 2.5 Pro ranges from $1.25 to $2.50/1M input tokens by tier; GPT-4o Search Preview costs $2.50/1M input tokens. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

Gemini 2.5 Pro fits 8x more tokens; pick it for long-context work and GPT-4o Search Preview for tighter calls.

Decision scorecard

Local evidence first
SignalGemini 2.5 ProGPT-4o Search Preview
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsgeneral production evaluation
Decision fitCoding, RAG, and AgentsRAG, Long context, and Classification
Context window1m128k
Cheapest output$10/1M tokens$10/1M tokens
Provider routes4 tracked1 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose Gemini 2.5 Pro when...
  • Gemini 2.5 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Gemini 2.5 Pro has broader tracked provider coverage for fallback and procurement flexibility.
  • Gemini 2.5 Pro uniquely exposes Vision, Multimodal, and Reasoning in local model data.
  • Local decision data tags Gemini 2.5 Pro for Coding, RAG, and Agents.
Choose GPT-4o Search Preview when...
  • Local decision data tags GPT-4o Search Preview for RAG, Long context, and Classification.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate Gemini 2.5 Pro

Gemini 2.5 Pro

$3,500

Cheapest tracked route/tier: Google AI Studio <=200K tokens

GPT-4o Search Preview

$4,500

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $1,000. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Gemini 2.5 Pro -> GPT-4o Search Preview
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Cheapest tracked output pricing is tied, so migration risk shifts to quality, latency, and provider packaging.
  • Check replacement coverage for Vision, Multimodal, and Reasoning before moving production traffic.
GPT-4o Search Preview -> Gemini 2.5 Pro
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Cheapest tracked output pricing is tied, so migration risk shifts to quality, latency, and provider packaging.
  • Gemini 2.5 Pro adds Vision, Multimodal, and Reasoning in local capability data.

Specs

Specification
Released2025-06-172025-02-26
Context window1m128k
Parameters
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryProprietary
OpennessProprietaryProprietary
Commercial useCommercial use: conditionalCommercial use: conditional
Knowledge cutoff2025-012023-10

Pricing and availability

Pricing attributeGemini 2.5 ProGPT-4o Search Preview
Input price
<=200K tokens
$1.25/1M tokens
Standard Gemini 2.5 Pro pricing for prompts up to 200K tokens.
>200K tokens
$2.50/1M tokens
Higher Gemini 2.5 Pro tier for prompts above 200K tokens.
$2.50/1M tokens
Output price
<=200K tokens
$10/1M tokens
Standard Gemini 2.5 Pro pricing for prompts up to 200K tokens.
>200K tokens
$15/1M tokens
Higher Gemini 2.5 Pro tier for prompts above 200K tokens.
$10/1M tokens
Providers

Capabilities

CapabilityGemini 2.5 ProGPT-4o Search Preview
VisionYesNo
MultimodalYesNo
ReasoningYesNo
Function callingYesNo
Tool useYesNo
Structured outputsYesYes
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark scores are currently available for this pair.

Deep dive

The capability footprint differs most on vision: Gemini 2.5 Pro, multimodal input: Gemini 2.5 Pro, reasoning mode: Gemini 2.5 Pro, function calling: Gemini 2.5 Pro, tool use: Gemini 2.5 Pro, and code execution: Gemini 2.5 Pro. 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 2.5 Pro lists tiered pricing: <=200K tokens is $1.25/1M input and $10/1M output; >200K tokens is $2.50/1M input and $15/1M output, while GPT-4o Search Preview lists $2.50/1M input and $10/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Gemini 2.5 Pro lower by about $0.88 per million blended tokens. For tiered rows, this cheapest-track view can understate interactive or fast-lane spend, so compare the tier you will actually use. Availability is 4 providers versus 1, so concentration risk also matters.

Choose Gemini 2.5 Pro when coding workflow support, larger context windows, and lower cheapest-tier input-token cost are central to the workload. Choose GPT-4o Search Preview when provider fit 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 2.5 Pro or GPT-4o Search Preview?

Gemini 2.5 Pro supports 1m tokens, while GPT-4o 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 2.5 Pro or GPT-4o Search Preview?

Gemini 2.5 Pro lists tiered pricing: <=200K tokens is $1.25/1M input and $10/1M output; >200K tokens is $2.50/1M input and $15/1M output. GPT-4o Search Preview lists $2.50/1M input and $10/1M output tokens on the cheapest tracked provider. Compare the tier you will actually use; cheap async pricing can overstate savings for interactive workflows. Provider discounts or batch pricing can still change the final bill.

Is Gemini 2.5 Pro or GPT-4o Search Preview open source?

Gemini 2.5 Pro is listed under Proprietary. GPT-4o Search Preview 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 2.5 Pro or GPT-4o Search Preview?

Gemini 2.5 Pro 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 2.5 Pro or GPT-4o Search Preview?

Gemini 2.5 Pro 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 2.5 Pro and GPT-4o Search Preview?

Gemini 2.5 Pro is available on Google AI Studio, GCP Vertex AI, OpenRouter, and Vercel AI Gateway. GPT-4o Search Preview is available on OpenRouter. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-15. Data sourced from public model cards and provider documentation.