Pairwise benchmark snapshot · Aug 16, 2026
In this head-to-head showdown, OpenAI o3-mini delivers higher overall intelligence and human-preferred responses (Elo 1,560 vs 1,466), while OpenAI o3-mini leads in SWE-bench software engineering benchmarks (78.5%), 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.
10 direct benchmark disciplines evaluated across capability, speed, and cost
OpenAI 5.6 fast/cheap tier. Official API $0.20/$1.20 per 1M after the Jul 30 80% Luna cut.
OpenAI cost-efficient reasoning model with adjustable thinking effort and top coding benchmark scores.
Currently comparing GPT-5.6 Luna vs OpenAI o3-mini. 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 94 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 | GPT-5.6 Luna | OpenAI o3-mini | Advantage Delta |
|---|---|---|---|
| Preference Elo | +94 | ||
| Coding Elo | +127 | ||
| LiveBench | +8.2% | ||
| SWE-bench | +16.7% | ||
| GPQA Diamond | +11.8% | ||
| Time to first token | +202 ms | ||
| Output speed | 188 tok/s | 92 tok/s | +96 tok/s |
| Input price | $1.1/1M | +$0.9/1M | |
| Output price | $4.4/1M | +$3.2/1M | |
| Context window | +800k |
Simulate monthly production API costs in USD (US Dollar).
GPT-5.6 Luna is estimated to save $79.50/month ($954/year).
Higher SWE-bench (78.5%).
Lower output list price ($1.2/1M).
Lower TTFT (88 ms).
Larger window (1M).
GPT-5.6 Luna is the side marked multimodal in the catalog.
| Target Workload | Recommended Pick | Evaluation Rationale |
|---|---|---|
| Repo / coding agents | OpenAI o3-mini | Higher SWE-bench (78.5%). |
| 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 | GPT-5.6 Luna | Larger window (1M). |
| Screenshots / vision | GPT-5.6 Luna | GPT-5.6 Luna is the side marked multimodal in the catalog. |
Luna is the OpenAI fast/cheap 5.6 SKU after Jul 30. It is not Sol. Sort by price and TTFT, not Elo.
High-volume agents that cannot pay Sol. Compare to Luna before you assume the new cheap SKU wins.
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