Llama Guard 3 8B vs Llama 3.1 405B
Llama Guard 3 8B (2024) and Llama 3.1 405B (2024) are compact production models from AI at Meta. Llama Guard 3 8B ships a 8K-token context window, while Llama 3.1 405B ships a 128K-token context window. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing. The goal is to make the tradeoff clear before deeper testing.
Llama 3.1 405B fits 16x more tokens; pick it for long-context work and Llama Guard 3 8B for tighter calls.
Specs
| Specification | ||
|---|---|---|
| Released | 2024-07-23 | 2024-07-23 |
| Context window | 8K | 128K |
| Parameters | 8B | 405B |
| Architecture | decoder only | decoder only |
| License | Open Source | Open Source |
| Knowledge cutoff | - | - |
Pricing and availability
| Pricing attribute | Llama Guard 3 8B | Llama 3.1 405B |
|---|---|---|
| Input price | $0.2/1M tokens | - |
| Output price | $0.2/1M tokens | - |
| Providers | - |
Capabilities
| Capability | Llama Guard 3 8B | Llama 3.1 405B |
|---|---|---|
| Vision | No | No |
| Multimodal | No | No |
| Reasoning | No | No |
| Function calling | No | No |
| Tool use | No | No |
| Structured outputs | Yes | No |
| Code execution | No | No |
Benchmarks
No shared benchmark rows are currently sourced for this pair.
Deep dive
The capability footprint differs most on structured outputs: Llama Guard 3 8B. 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.
Pricing coverage is uneven: Llama Guard 3 8B has $0.2/1M input tokens and Llama 3.1 405B has no token price sourced yet. Provider availability is 4 tracked routes versus 0. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.
Choose Llama Guard 3 8B when provider fit and broader provider choice are central to the workload. Choose Llama 3.1 405B when long-context analysis 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. For teams standardizing a stack, that distinction is often the difference between a benchmark win and a reliable deployment.
FAQ
Which has a larger context window, Llama Guard 3 8B or Llama 3.1 405B?
Llama 3.1 405B supports 128K tokens, while Llama Guard 3 8B supports 8K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Is Llama Guard 3 8B or Llama 3.1 405B open source?
Llama Guard 3 8B is listed under Open Source. Llama 3.1 405B 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, Llama Guard 3 8B or Llama 3.1 405B?
Llama Guard 3 8B 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 Llama Guard 3 8B and Llama 3.1 405B?
Llama Guard 3 8B is available on Microsoft Foundry, OpenRouter, Fireworks AI, and Replicate API. Llama 3.1 405B is available on the tracked providers still being sourced. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
When should I pick Llama Guard 3 8B over Llama 3.1 405B?
Llama 3.1 405B fits 16x more tokens; pick it for long-context work and Llama Guard 3 8B for tighter calls. If your workload also depends on provider fit, start with Llama Guard 3 8B; if it depends on long-context analysis, run the same evaluation with Llama 3.1 405B.
Continue comparing
Last reviewed: 2026-05-11. Data sourced from public model cards and provider documentation.