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Llama 4 405B vs o3

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

Updated

Llama 4 405B specs · o3 specs
Verdict by category
  • Priceo3

    o3 publishes pricing ($8.00 / 1M output tokens) while Llama 4 405B does not.

  • Context windowLlama 4 405B

    Llama 4 405B accepts 256K tokens vs 200K, 1.3× the room for long documents and codebases.

  • BenchmarksTie

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

  • ModalitiesTie

    Both handle text, vision.

  • OpennessLlama 4 405B

    Llama 4 405B ships open weights (Llama 4 Community License); o3 is API-only.

On balance Llama 4 405B edges ahead, winning 2 of 5 categories against o3's 1. o3 publishes pricing ($8.00 / 1M output tokens) while Llama 4 405B does not. Llama 4 405B accepts 256K tokens vs 200K, 1.3× the room for long documents and codebases.

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, vision), so the deciding factors are price, context, and raw quality. Llama 4 405B ships open weights (Llama 4 Community License); o3 is API-only.

Both shipped within roughly a month of each other in 2025, so they share the same generation of training data and tooling. Llama 4 405B is usually picked for open source llm and fine tuning workloads, while o3 sees more deployments in reasoning and math. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

SpecLlama 4 405Bo3
ProviderMetaOpenAI
ReleasedApr 2025Apr 2025
Modalitiestext, visiontext, vision
Context window256K tokens200K tokens
Max output,,
Input · 1MPricing not published$2.00 / 1M tokens
Output · 1MPricing not published$8.00 / 1M tokens
Knowledge cutoff2024-122024-06
Open weightsYes (Llama 4 Community License)No
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 $18.00
  • Heavy usage, 1M in / 500k out per day, vs $180
  • RAG workload, 5M in / 200k out per day, vs $348

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 4 405BPricing unavailable
  • o3$0.600

Benchmarks compared

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

Llama 4 405Bo3
  • HumanEval,95.0
  • GPQA,87.7
Pick Llama 4 405B if

Llama 4 405B fits when…

  • Strongest open-weight model at launch
  • Multimodal (text + vision)
  • Wide hosting availability
  • Self-hosting and on-prem requirements, open weights (Llama 4 Community License).
Pick o3 if

o3 fits when…

  • Industry-leading reasoning depth at launch
  • Strong on math, science, and abstract puzzles
  • Tool-use during reasoning loops
Don't want either?

Consider Llama 4 70B

Meta's mid-tier Llama 4, the practical workhorse for self-hosted deployments.

See Llama 4 70B specsLlama 4 405B vs Llama 4 70Bo3 vs Llama 4 70B

Frequently asked

  • Is Llama 4 405B or o3 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?
    Llama 4 405B accepts 256K tokens vs 200K for o3.
  • Is Llama 4 405B or o3 better for coding?
    Both Llama 4 405B and o3 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?
    Llama 4 405B ships open weights (Llama 4 Community License). o3 is API-only.
  • When were Llama 4 405B and o3 released?
    Llama 4 405B was released by Meta on 2025-04-05. o3 was released by OpenAI on 2025-04-16.
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