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Gemini 3 Flash Preview vs GPT-5.4

Gemini 3 Flash Preview (2025) and GPT-5.4 (2026) are frontier reasoning models from Google DeepMind and OpenAI. Gemini 3 Flash Preview ships a 1M-token context window, while GPT-5.4 ships a 1.1M-token context window. On pricing, Gemini 3 Flash Preview costs $0.5/1M input tokens versus $2.5/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.

Gemini 3 Flash Preview is ~400% cheaper at $0.5/1M; pay for GPT-5.4 only for coding workflow support.

Decision scorecard

Local evidence first
SignalGemini 3 Flash PreviewGPT-5.4
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window1M1.1M
Cheapest output$3/1M tokens$15/1M tokens
Provider routes3 tracked2 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose Gemini 3 Flash Preview when...
  • Gemini 3 Flash Preview has the lower cheapest tracked output price at $3/1M tokens.
  • Gemini 3 Flash Preview has broader tracked provider coverage for fallback and procurement flexibility.
  • Gemini 3 Flash Preview uniquely exposes Vision in local model data.
  • Local decision data tags Gemini 3 Flash Preview for Coding, RAG, and Agents.
Choose GPT-5.4 when...
  • GPT-5.4 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • GPT-5.4 uniquely exposes Reasoning in local model data.
  • Local decision data tags GPT-5.4 for Coding, RAG, and Agents.

Monthly cost at traffic

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

Lower estimate Gemini 3 Flash Preview

Gemini 3 Flash Preview

$1,150

Cheapest tracked route: GCP Vertex AI

GPT-5.4

$5,750

Cheapest tracked route: OpenAI API

Estimated monthly gap: $4,600. Batch, cache, and negotiated pricing are excluded from this local estimate.

Switch friction

Gemini 3 Flash Preview -> GPT-5.4
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • GPT-5.4 is $12/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Check replacement coverage for Vision before moving production traffic.
  • GPT-5.4 adds Reasoning in local capability data.
GPT-5.4 -> Gemini 3 Flash Preview
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Gemini 3 Flash Preview is $12/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Reasoning before moving production traffic.
  • Gemini 3 Flash Preview adds Vision in local capability data.

Specs

Specification
Released2025-12-172026-03-05
Context window1M1.1M
Parameters
Architecturedecoder onlydecoder only
LicenseProprietaryProprietary
Knowledge cutoff2025-012025-08

Pricing and availability

Pricing attributeGemini 3 Flash PreviewGPT-5.4
Input price$0.5/1M tokens$2.5/1M tokens
Output price$3/1M tokens$15/1M tokens
Providers

Capabilities

CapabilityGemini 3 Flash PreviewGPT-5.4
VisionYesNo
MultimodalYesYes
ReasoningNoYes
Function callingYesYes
Tool useYesYes
Structured outputsYesYes
Code executionYesYes

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on vision: Gemini 3 Flash Preview and reasoning mode: GPT-5.4. Both models share multimodal input, function calling, tool use, and 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 Flash Preview lists $0.5/1M input and $3/1M output tokens, while GPT-5.4 lists $2.5/1M input and $15/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Gemini 3 Flash Preview lower by about $5 per million blended tokens. Availability is 3 providers versus 2, so concentration risk also matters.

Choose Gemini 3 Flash Preview when coding workflow support, lower input-token cost, and broader provider choice are central to the workload. Choose GPT-5.4 when coding workflow support and larger context windows 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

Which has a larger context window, Gemini 3 Flash Preview or GPT-5.4?

GPT-5.4 supports 1.1M tokens, while Gemini 3 Flash Preview supports 1M 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 Flash Preview or GPT-5.4?

Gemini 3 Flash Preview is cheaper on tracked token pricing. Gemini 3 Flash Preview costs $0.5/1M input and $3/1M output tokens. GPT-5.4 costs $2.5/1M input and $15/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is Gemini 3 Flash Preview or GPT-5.4 open source?

Gemini 3 Flash Preview is listed under Proprietary. GPT-5.4 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 Flash Preview or GPT-5.4?

Gemini 3 Flash 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 Flash Preview or GPT-5.4?

Both Gemini 3 Flash Preview and GPT-5.4 expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.

Where can I run Gemini 3 Flash Preview and GPT-5.4?

Gemini 3 Flash Preview is available on GCP Vertex AI, OpenRouter, and Google AI Studio. GPT-5.4 is available on OpenAI API and 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.