MetaLlama-3.1 405BVSOpenAIGPT-5.5
Our Take
We recommend GPT-5.5 if you need peak intelligence and a much larger context window for full-repo analysis, or the free Llama-3.1 405B if you want zero API costs and total offline privacy. While GPT-5.5 offers superior reasoning capability, Llama-3.1 405B runs entirely on your own local hardware. Choose GPT-5.5 for repository-scale analysis, or Llama-3.1 405B for zero-cost offline privacy and basic standalone code completion and simple functions.
▶WHY?
Benchmark Calculations & Evidence:
Reasoning Accuracy: Both models were evaluated on the GPQA Diamond benchmark. GPT-5.5 scored 93.6%, while Llama-3.1 405B scored 50.7% (+42.9% gap).
Coding Performance: Evaluated on different benchmarks. Llama-3.1 405B scored 89% on HumanEval (basic standalone code completion and simple functions), while GPT-5.5 scored 58.6% on SWE-bench Pro (complex codebases, multi-file repositories, and architectural planning).
Context Window: GPT-5.5 supports a 1M context window, while Llama-3.1 405B supports 131k.
Hosting Model: Llama-3.1 405B runs locally for $0 API costs, while GPT-5.5 is a cloud API.
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Benchmarks & Scores
Coding (human-eval)
89%basic standalone code completion and simple functions
Reasoning (gpqa-diamond)
50.7%graduate-level science QA
Cost & Context
Cost (per 1M tokens)
Self HostLocal execution (zero API fees)Context Window
131.07k tokensBenchmarks & Scores
Coding (swe-bench-pro)
58.6%complex codebases, multi-file repositories, and architectural planning
Reasoning (gpqa-diamond)Winner (+42.9%)
93.6%graduate-level science QA
Cost & Context
Cost (per 1M tokens)
$11.25Input: $5.00 | Output: $30.00Context WindowLarger
1.05M tokensFrequently Asked Questions about Llama-3.1 405B vs GPT-5.5
For coding tasks, Llama-3.1 405B scores 89% on human-eval (basic standalone code completion and simple functions), while GPT-5.5 scores 58.6% on swe-bench-pro (complex codebases, multi-file repositories, and architectural planning).
Related Matchups
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