Pairwise benchmark snapshot · Aug 1, 2026
In this head-to-head showdown, Claude Opus 4.5 delivers higher overall intelligence and human-preferred responses (Elo 1,568 vs 1,370), while Claude Opus 4.5 leads in SWE-bench software engineering benchmarks (76.8%), while Llama 3.1 405B is more budget-friendly at $3.5/1M per 1M output tokens, while Claude Opus 4.5 provides faster response streaming (62 tok/s). Review the complete breakdown below to determine which model best fits your performance and budget requirements.
10 direct benchmark disciplines evaluated across capability, speed, and cost
Anthropic frontier coding and computer-use model. SWE-bench leader on the official mini-SWE-agent harness in the Feb 2026 refresh.
Meta flagship open-weight 405B dense foundation model with 128k context window.
Simulate accuracy gains vs added response time & token cost
Reasoning models “think before answering” by generating internal reasoning tokens. Higher effort improves math, coding, and logic accuracy, but increases response delay and token costs.
Δ 198 Arena Elo pts
62 tok/s
$3.5 / 1M output
Relative percentile scores computed across all active models in the benchmark catalog.
Comparing top Western standard models with China's leading frontier rival across 6 skill dimensions. Tap any spoke or dot to inspect.
Category wins across reasoning intelligence, generation speed, and token cost.
Preference Elo, Coding proficiency, SWE-bench & LiveBench accuracy
Generation throughput and time to first token responsiveness
Cost per million tokens and max context window length
| Benchmark | Claude Opus 4.5 | Llama 3.1 405B | Advantage Delta |
|---|---|---|---|
| Preference Elo | +198 | ||
| Coding Elo | +189 | ||
| LiveBench | +10% | ||
| SWE-bench | +18.4% | ||
| GPQA Diamond | +8.9% | ||
| Time to first token | +20 ms | ||
| Output speed | 62 tok/s | 42 tok/s | +20 tok/s |
| Input price | $1.25/1M | +$13.75/1M | |
| Output price | $3.5/1M | +$71.5/1M | |
| Context window | +72k |
Simulate monthly production API costs in USD (US Dollar).
Llama 3.1 405B is estimated to save $1,553.75/month ($18,645/year).
Higher SWE-bench (76.8%).
Lower output list price ($3.5/1M).
Lower TTFT (360 ms).
Larger window (200k).
Claude Opus 4.5 is the side marked multimodal in the catalog.
| Target Workload | Recommended Pick | Evaluation Rationale |
|---|---|---|
| Repo / coding agents | Claude Opus 4.5 | Higher SWE-bench (76.8%). |
| High-volume chat | Llama 3.1 405B | Lower output list price ($3.5/1M). |
| Voice / low-latency UI | Llama 3.1 405B | Lower TTFT (360 ms). |
| Long-document RAG | Claude Opus 4.5 | Larger window (200k). |
| Screenshots / vision | Claude Opus 4.5 | Claude Opus 4.5 is the side marked multimodal in the catalog. |
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