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Llama 3.1 405B vs Llama 4 8B

A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.

Updated

Llama 3.1 405B specs · Llama 4 8B specs
Verdict by category
  • PriceTie

    Neither model publishes per-token API pricing.

  • Context windowTie

    Both ship a 128K-token context window.

  • BenchmarksTie

    No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores.

  • ModalitiesTie

    Both handle text.

  • OpennessTie

    Both ship open weights, self-host either one.

It's a genuine coin-flip between Llama 3.1 405B and Llama 4 8B: 0 category wins each, with the rest tied. Neither model publishes per-token API pricing. Both ship a 128K-token context window.

No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. Both target the same set of modalities (text), so the deciding factors are price, context, and raw quality. Both ship open weights, self-host either one.

Llama 4 8B is the newer of the two, released 9 months after Llama 3.1 405B, which usually means a more recent knowledge cutoff and updated safety post-training. Llama 3.1 405B is usually picked for open source llm and fine tuning workloads, while Llama 4 8B sees more deployments in local llm and on device. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

SpecLlama 3.1 405BLlama 4 8B
ProviderMetaMeta
ReleasedJul 2024Apr 2025
Modalitiestexttext
Context window128K tokens128K tokens
Max output,,
Input · 1MPricing not publishedPricing not published
Output · 1MPricing not publishedPricing not published
Knowledge cutoff,,
Open weightsYes (Llama 3 Community License)Yes (Llama 4 Community License)
API availableYesYes

Pricing at scale

What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.

  • Light usage, 100k in / 50k out per day, vs ,
  • Heavy usage, 1M in / 500k out per day, vs ,
  • RAG workload, 5M in / 200k out per day, vs ,

Light usage, 100k in / 50k out per day: pricing not directly comparable (one or both models are missing public per-token rates). Heavy usage, 1M in / 500k out per day: pricing not directly comparable (one or both models are missing public per-token rates). RAG workload, 5M in / 200k out per day: pricing not directly comparable (one or both models are missing public per-token rates).

Price calculator

Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.

  • Llama 3.1 405BPricing unavailable
  • Llama 4 8BPricing unavailable

Benchmarks compared

Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.

Llama 3.1 405BLlama 4 8B
  • MMLU88.6
  • HumanEval89.0
Pick Llama 3.1 405B if

Llama 3.1 405B fits when…

  • Historic milestone for open-weight quality
  • Wide hosting availability
Pick Llama 4 8B if

Llama 4 8B fits when…

  • Runs on consumer laptops
  • Broad tooling support
  • Apache-2-adjacent permissiveness for most uses
Don't want either?

Consider Llama 4 405B

Meta's flagship open-weight model, sparse MoE design competitive with closed-frontier flagships.

See Llama 4 405B specsLlama 3.1 405B vs Llama 4 405BLlama 4 8B vs Llama 4 405B

Frequently asked

  • Is Llama 3.1 405B or Llama 4 8B cheaper?
    Per-token pricing isn't published for at least one of these models, check each model's spec page for current rates.
  • Which has the larger context window?
    Both Llama 3.1 405B and Llama 4 8B ship a 128K-token context window.
  • Is Llama 3.1 405B or Llama 4 8B better for coding?
    Both Llama 3.1 405B and Llama 4 8B are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.
  • Are either of these models open source?
    Both ship with open weights. Llama 3.1 405B is licensed under Llama 3 Community License; Llama 4 8B under Llama 4 Community License.
  • When were Llama 3.1 405B and Llama 4 8B released?
    Llama 3.1 405B was released by Meta on 2024-07-23. Llama 4 8B was released by Meta on 2025-04-05.
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