Pairwise benchmark snapshot · Aug 16, 2026
In this head-to-head showdown, Claude Opus 5 delivers higher overall intelligence and human-preferred responses (Elo 1,624 vs 1,466), while Claude Opus 5 leads in SWE-bench software engineering benchmarks (79.2%), while GPT-5.6 Luna is more budget-friendly at $1.2/1M per 1M output tokens. Review the complete breakdown below to determine which model best fits your performance and budget requirements.
9 direct benchmark disciplines evaluated across capability, speed, and cost
Anthropic current default flagship. Official API $5/$25 per 1M tokens and a 1M context window (Anthropic, Jul 24 2026).
OpenAI 5.6 fast/cheap tier. Official API $0.20/$1.20 per 1M after the Jul 30 80% Luna cut.
Currently comparing Claude Opus 5 vs GPT-5.6 Luna. Alternative family tiers available.
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 158 Arena Elo pts
188 tok/s
$1.2 / 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 5 | GPT-5.6 Luna | Advantage Delta |
|---|---|---|---|
| Preference Elo | +158 | ||
| Coding Elo | +160 | ||
| LiveBench | +10.6% | ||
| SWE-bench | +17.4% | ||
| GPQA Diamond | +11.7% | ||
| Time to first token | +222 ms | ||
| Output speed | 72 tok/s | 188 tok/s | +116 tok/s |
| Input price | +$4.8/1M | ||
| Output price | +$23.8/1M | ||
| Context window | — |
Simulate monthly production API costs in USD (US Dollar).
GPT-5.6 Luna is estimated to save $525.00/month ($6,300/year).
Higher SWE-bench (79.2%).
Lower output list price ($1.2/1M).
Lower TTFT (88 ms).
Larger window (1M).
Both accept images. Defaulting to the higher-Elo side (Claude Opus 5).
| Target Workload | Recommended Pick | Evaluation Rationale |
|---|---|---|
| Repo / coding agents | Claude Opus 5 | Higher SWE-bench (79.2%). |
| High-volume chat | GPT-5.6 Luna | Lower output list price ($1.2/1M). |
| Voice / low-latency UI | GPT-5.6 Luna | Lower TTFT (88 ms). |
| Long-document RAG | Claude Opus 5 | Larger window (1M). |
| Screenshots / vision | Claude Opus 5 | Both accept images. Defaulting to the higher-Elo side (Claude Opus 5). |
Usually Sonnet 5 vs Opus 5. Coding delta versus output $/1M. The workhorse question.
Luna is the OpenAI fast/cheap 5.6 SKU after Jul 30. It is not Sol. Sort by price and TTFT, not Elo.
Top Anthropic vs top Google. Usually Opus 5 vs 3.6 Pro. Two different invoices.
Not a frozen 2025 article. Today that is usually Opus 5 vs GPT-5.6 Sol. Dated cells, not a brand fight.
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Verified Head-to-Head Telemetry
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