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Gemini 3 Flash Preview vs Llama 3.1 405B Instruct

Gemini 3 Flash Preview (2025) and Llama 3.1 405B Instruct (2024) are compact production models from Google DeepMind and AI at Meta. Gemini 3 Flash Preview ships a 1M-token context window, while Llama 3.1 405B Instruct ships a 128K-token context window. On pricing, Gemini 3 Flash Preview costs $0.5/1M input tokens versus $2.4/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.

Gemini 3 Flash Preview is ~380% cheaper at $0.5/1M; pay for Llama 3.1 405B Instruct only for provider fit.

Decision scorecard

Local evidence first
SignalGemini 3 Flash PreviewLlama 3.1 405B Instruct
Decision fitCoding, RAG, and AgentsRAG, Long context, and Classification
Context window1M128K
Cheapest output$3/1M tokens$2.4/1M tokens
Provider routes3 tracked11 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose Gemini 3 Flash Preview when...
  • Gemini 3 Flash Preview has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Gemini 3 Flash Preview uniquely exposes Vision, Multimodal, and Function calling in local model data.
  • Local decision data tags Gemini 3 Flash Preview for Coding, RAG, and Agents.
Choose Llama 3.1 405B Instruct when...
  • Llama 3.1 405B Instruct has the lower cheapest tracked output price at $2.4/1M tokens.
  • Llama 3.1 405B Instruct has broader tracked provider coverage for fallback and procurement flexibility.
  • Local decision data tags Llama 3.1 405B Instruct 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 Gemini 3 Flash Preview

Gemini 3 Flash Preview

$1,150

Cheapest tracked route: GCP Vertex AI

Llama 3.1 405B Instruct

$2,520

Cheapest tracked route: AWS Bedrock

Estimated monthly gap: $1,370. Batch, cache, and negotiated pricing are excluded from this local estimate.

Switch friction

Gemini 3 Flash Preview -> Llama 3.1 405B Instruct
  • Provider overlap exists on GCP Vertex AI; start route-level A/B tests there.
  • Llama 3.1 405B Instruct is $0.6/1M 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.
Llama 3.1 405B Instruct -> Gemini 3 Flash Preview
  • Provider overlap exists on GCP Vertex AI; start route-level A/B tests there.
  • Gemini 3 Flash Preview is $0.6/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Gemini 3 Flash Preview adds Vision, Multimodal, and Function calling in local capability data.

Specs

Specification
Released2025-12-172024-07-23
Context window1M128K
Parameters405B
Architecturedecoder onlydecoder only
LicenseProprietaryOpen Source
Knowledge cutoff2025-01-

Pricing and availability

Pricing attributeGemini 3 Flash PreviewLlama 3.1 405B Instruct
Input price$0.5/1M tokens$2.4/1M tokens
Output price$3/1M tokens$2.4/1M tokens
Providers

Capabilities

CapabilityGemini 3 Flash PreviewLlama 3.1 405B Instruct
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 Flash Preview, multimodal input: Gemini 3 Flash Preview, function calling: Gemini 3 Flash Preview, tool use: Gemini 3 Flash Preview, and code execution: Gemini 3 Flash 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 Flash Preview lists $0.5/1M input and $3/1M output tokens, while Llama 3.1 405B Instruct lists $2.4/1M input and $2.4/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Gemini 3 Flash Preview lower by about $1.15 per million blended tokens. Availability is 3 providers versus 11, so concentration risk also matters.

Choose Gemini 3 Flash Preview when coding workflow support, larger context windows, and lower input-token cost are central to the workload. Choose Llama 3.1 405B Instruct when provider fit and broader provider choice 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 Flash Preview or Llama 3.1 405B Instruct?

Gemini 3 Flash Preview supports 1M tokens, while Llama 3.1 405B Instruct 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 Flash Preview or Llama 3.1 405B Instruct?

Gemini 3 Flash Preview is cheaper on tracked token pricing. Gemini 3 Flash Preview costs $0.5/1M input and $3/1M output tokens. Llama 3.1 405B Instruct costs $2.4/1M input and $2.4/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is Gemini 3 Flash Preview or Llama 3.1 405B Instruct open source?

Gemini 3 Flash Preview is listed under Proprietary. Llama 3.1 405B Instruct is listed under Open Source. 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 Llama 3.1 405B Instruct?

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 Llama 3.1 405B Instruct?

Gemini 3 Flash 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 Flash Preview and Llama 3.1 405B Instruct?

Gemini 3 Flash Preview is available on GCP Vertex AI, OpenRouter, and Google AI Studio. Llama 3.1 405B Instruct is available on OctoAI API (Deprecated), Together AI, Fireworks AI, IBM watsonx, and Scale AI GenAI Platform. 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.