GPT-5 vs Llama 4 405B for debugging: which is better in 2026?
A head-to-head look at GPT-5 and Llama 4 405B for debugging. Benchmarks via artificialanalysis.ai, pricing as of May 2026. Compare AI models like these inside Admix.
Quick verdict
For debugging in May 2026, GPT-5 edges out Llama 4 405B on the codingIndex metric. Top reasoning and math scores.
Side-by-side specs
| Spec | GPT-5 | Llama |
|---|---|---|
| Intelligence index | 78.4 | 71.5 |
| Coding index | 76.1 | 69.0 |
| Context window | 400K tokens | 256K tokens |
| Speed (tok/s) | 142 | 95 |
| Input $/M | $5.00 | $0.90 |
| Output $/M | $20.00 | $2.70 |
| Released | Aug 7, 2025 | Nov 5, 2025 |
How they handle debugging
GPT-5: Top reasoning and math scores. The main caveat is more expensive than mid-tier models.
Llama 4 405B: Best fully open-weights model. The main caveat is trails closed flagships on coding.
Cost per 1,000 queries
Assuming 1,500 input and 800 output tokens per query:
- GPT-5: $23.50 per 1,000 queries
- Llama 4 405B: $3.51 per 1,000 queries
Verdict by sub-task
- Best raw quality on debugging:
- Best price: Llama 4 405B
- Longest context: GPT-5
- Fastest: GPT-5
FAQ
Is GPT-5 better than Llama 4 405B for debugging?
On May 2026 benchmarks (artificialanalysis.ai), GPT-5 ranks higher than Llama 4 405B for debugging on the codingIndex metric. The gap is small enough that the choice often comes down to price, context length, and tone.
Which is cheaper, GPT-5 or Llama 4 405B?
GPT-5 costs $5.00 input and $20.00 output per million tokens. Llama 4 405B costs $0.90 input and $2.70 output per million tokens.
Can I use both GPT-5 and Llama in one app?
Yes. Admix is a multi model AI chat aggregator that lets you run GPT-5 and Llama 4 405B side by side under one subscription.
Sources
Benchmarks from artificialanalysis.ai (May 2026).
Related
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