LLM ReferenceLLM Reference

Gemini 1.5 Flash 8B vs Llama 3.1 405B Instruct

Gemini 1.5 Flash 8B (2024) and Llama 3.1 405B Instruct (2024) are compact production models from Google DeepMind and AI at Meta. Gemini 1.5 Flash 8B ships a not-yet-sourced context window, while Llama 3.1 405B Instruct ships a 128K-token context window. On pricing, Gemini 1.5 Flash 8B costs $0.04/1M input tokens versus $2.4/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.

Gemini 1.5 Flash 8B is ~6300% cheaper at $0.04/1M; pay for Llama 3.1 405B Instruct only for provider fit.

Decision scorecard

Local evidence first
SignalGemini 1.5 Flash 8BLlama 3.1 405B Instruct
Decision fitGeneralRAG, Long context, and Classification
Context window128K
Cheapest output$0.15/1M tokens$2.4/1M tokens
Provider routes1 tracked11 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose Gemini 1.5 Flash 8B when...
  • Gemini 1.5 Flash 8B has the lower cheapest tracked output price at $0.15/1M tokens.
Choose Llama 3.1 405B Instruct when...
  • Llama 3.1 405B Instruct has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Llama 3.1 405B Instruct has broader tracked provider coverage for fallback and procurement flexibility.
  • Llama 3.1 405B Instruct uniquely exposes Structured outputs in local model data.
  • 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 1.5 Flash 8B

Gemini 1.5 Flash 8B

$67.50

Cheapest tracked route: GCP Vertex AI

Llama 3.1 405B Instruct

$2,520

Cheapest tracked route: AWS Bedrock

Estimated monthly gap: $2,453. Batch, cache, and negotiated pricing are excluded from this local estimate.

Switch friction

Gemini 1.5 Flash 8B -> 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 $2.25/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Llama 3.1 405B Instruct adds Structured outputs in local capability data.
Llama 3.1 405B Instruct -> Gemini 1.5 Flash 8B
  • Provider overlap exists on GCP Vertex AI; start route-level A/B tests there.
  • Gemini 1.5 Flash 8B is $2.25/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Structured outputs before moving production traffic.

Specs

Specification
Released2024-10-032024-07-23
Context window128K
Parameters8B405B
Architecturedecoder onlydecoder only
LicenseUnknownOpen Source
Knowledge cutoff--

Pricing and availability

Pricing attributeGemini 1.5 Flash 8BLlama 3.1 405B Instruct
Input price$0.04/1M tokens$2.4/1M tokens
Output price$0.15/1M tokens$2.4/1M tokens
Providers

Capabilities

CapabilityGemini 1.5 Flash 8BLlama 3.1 405B Instruct
VisionNoNo
MultimodalNoNo
ReasoningNoNo
Function callingNoNo
Tool useNoNo
Structured outputsNoYes
Code executionNoNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on structured outputs: Llama 3.1 405B Instruct. Both models share the core language-model surface, 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 1.5 Flash 8B lists $0.04/1M input and $0.15/1M 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 1.5 Flash 8B lower by about $2.33 per million blended tokens. Availability is 1 providers versus 11, so concentration risk also matters.

Choose Gemini 1.5 Flash 8B when provider fit 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. 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 is cheaper, Gemini 1.5 Flash 8B or Llama 3.1 405B Instruct?

Gemini 1.5 Flash 8B is cheaper on tracked token pricing. Gemini 1.5 Flash 8B costs $0.04/1M input and $0.15/1M 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 1.5 Flash 8B or Llama 3.1 405B Instruct open source?

Gemini 1.5 Flash 8B is listed under Unknown. 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 structured outputs, Gemini 1.5 Flash 8B or Llama 3.1 405B Instruct?

Llama 3.1 405B Instruct has the clearer documented structured outputs signal in this comparison. If structured outputs is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run Gemini 1.5 Flash 8B and Llama 3.1 405B Instruct?

Gemini 1.5 Flash 8B is available on GCP Vertex AI. 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.

When should I pick Gemini 1.5 Flash 8B over Llama 3.1 405B Instruct?

Gemini 1.5 Flash 8B is ~6300% cheaper at $0.04/1M; pay for Llama 3.1 405B Instruct only for provider fit. If your workload also depends on provider fit, start with Gemini 1.5 Flash 8B; if it depends on provider fit, run the same evaluation with Llama 3.1 405B Instruct.

Continue comparing

Last reviewed: 2026-05-16. Data sourced from public model cards and provider documentation.