Pairwise benchmark snapshot · Aug 16, 2026
In this head-to-head showdown, Gemini 3.6 Flash delivers higher overall intelligence and human-preferred responses (Elo 1,506 vs 1,466), while Gemini 3.6 Flash leads in SWE-bench software engineering benchmarks (70.8%), while GPT-5.6 Luna is more budget-friendly at $1.2/1M per 1M output tokens, while Gemini 3.6 Flash provides faster response streaming (198 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
Google Jul 21 workhorse. Now shares the 3.7 Flash introductory $0.75/$3.75 rate through Dec 31 2026.
OpenAI 5.6 fast/cheap tier. Official API $0.20/$1.20 per 1M after the Jul 30 80% Luna cut.
Currently comparing Gemini 3.6 Flash vs GPT-5.6 Luna. Alternative family tiers available.
Δ 40 Arena Elo pts
198 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 | Gemini 3.6 Flash | GPT-5.6 Luna | Advantage Delta |
|---|---|---|---|
| Preference Elo | +40 | ||
| Coding Elo | +56 | ||
| LiveBench | +3% | ||
| SWE-bench | +9% | ||
| GPQA Diamond | +4.2% | ||
| Time to first token | +4 ms | ||
| Output speed | 198 tok/s | 188 tok/s | +10 tok/s |
| Input price | $0.75/1M | +$0.55/1M | |
| Output price | $3.75/1M | +$2.55/1M | |
| Context window | +49k |
Simulate monthly production API costs in USD (US Dollar).
GPT-5.6 Luna is estimated to save $57.50/month ($690/year).
Higher SWE-bench (70.8%).
Lower output list price ($1.2/1M).
Lower TTFT (88 ms).
Larger window (1M).
Both accept images. Defaulting to the higher-Elo side (Gemini 3.6 Flash).
| Target Workload | Recommended Pick | Evaluation Rationale |
|---|---|---|
| Repo / coding agents | Gemini 3.6 Flash | Higher SWE-bench (70.8%). |
| 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 | Gemini 3.6 Flash | Larger window (1M). |
| Screenshots / vision | Gemini 3.6 Flash | Both accept images. Defaulting to the higher-Elo side (Gemini 3.6 Flash). |
Jul 21 workhorse that inherited $0.75/$3.75 through year-end. Keep the row; 3.7 is the newer sibling.
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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Verified Head-to-Head Telemetry