Leaderboard · Compare · Llama 3.1 405B Instruct vs DeepSeek V3 · Updated
Llama 3.1 405B Instruct vs DeepSeek V3
DeepSeek V3 edges out Llama 3.1 405B Instruct on the composite (68.0 vs 65.7). The gap is meaningful but not decisive — see the per-benchmark breakdown below.
At a glance
| Spec | Llama 3.1 405B Instruct | DeepSeek V3 |
|---|---|---|
| Provider | Meta | DeepSeek |
| Released | 2024-07 | 2024-12 |
| Tier | open-weights | open-weights |
| License | Open · Llama 3.1 Community License | Open · DeepSeek License |
| Context window | 128k | 128k |
| $ in / out (per 1M) | $2.70 / $2.70 | $0.27 / $1.10 |
Benchmark scoreboard
Higher is better on every benchmark. Δ shows Llama 3.1 405B Instruct − DeepSeek V3.
| Benchmark | Llama 3.1 405B Instruct | DeepSeek V3 | Δ |
|---|---|---|---|
| Chatbot Arena Elo | 1267 | 1320 | -53 |
| MMLU-Pro | 73.3 | 75.9 | -2.6 |
| GPQA Diamond | 51.1 | 59.1 | -8.0 |
| MATH | 73.8 | 90.2 | -16.4 |
| HumanEval | 89.0 | 91.0 | -2.0 |
| SWE-Bench Verified | N/A | 42.0 | — |
Numbers compiled from provider technical reports and Chatbot Arena snapshots — see methodology.
OpenRouter routes Llama 3.1 405B Instruct, DeepSeek V3, and 100+ other LLMs behind a single API key — pay-as-you-go, no monthly minimum, fallback if a provider is down. Try OpenRouter → (affiliate · supports this site)
Llama 3.1 405B Instruct vs DeepSeek V3: where each one wins
Llama 3.1 405B Instruct is stronger on
No benchmarks where Llama 3.1 405B Instruct beats DeepSeek V3 with comparable data.
DeepSeek V3 is stronger on
- Arena
- MMLU-Pro
- GPQA
- MATH
- HumanEval
Cost comparison
At 10M tokens/day (50/50 split), Llama 3.1 405B Instruct costs ~$27.00/day vs $6.85/day for DeepSeek V3 — DeepSeek V3 is the cheaper pick at this volume.
Verdict
DeepSeek V3 edges out Llama 3.1 405B Instruct on the composite (68.0 vs 65.7). The gap is meaningful but not decisive — see the per-benchmark breakdown below.
If you can only pick one and your workload is unclear, route via OpenRouter and switch by request — same key, no lock-in.
Frequently asked questions
Which is better, Llama 3.1 405B Instruct or DeepSeek V3?
DeepSeek V3 edges out Llama 3.1 405B Instruct on the composite (68.0 vs 65.7). The gap is meaningful but not decisive — see the per-benchmark breakdown below. Llama 3.1 405B Instruct wins on no benchmarks; DeepSeek V3 wins on Arena, MMLU-Pro, GPQA, MATH, HumanEval.
What does Llama 3.1 405B Instruct cost compared to DeepSeek V3?
At 10M tokens/day (50/50 split), Llama 3.1 405B Instruct costs ~$27.00/day vs $6.85/day for DeepSeek V3 — DeepSeek V3 is the cheaper pick at this volume.
What is the context window of Llama 3.1 405B Instruct vs DeepSeek V3?
Llama 3.1 405B Instruct: 128k tokens. DeepSeek V3: 128k tokens.
Is Llama 3.1 405B Instruct or DeepSeek V3 open source?
Llama 3.1 405B Instruct: open weights (Llama 3.1 Community License). DeepSeek V3: open weights (DeepSeek License).
Can I try Llama 3.1 405B Instruct and DeepSeek V3 on the same API key?
Yes — OpenRouter routes both models behind a single key, so you can A/B test Llama 3.1 405B Instruct against DeepSeek V3 without juggling provider accounts.
Model deep-dives: Llama 3.1 405B Instruct · DeepSeek V3 · Full leaderboard
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