token.app › Compare › Gemini 3.5 Flash vs GPT-5.6 Luna
Gemini 3.5 Flash vs GPT-5.6 Luna
GPT-5.6 Luna leads on 3 of 5 shared benchmarks. GPT-5.6 Luna is 15× cheaper per token on a blended 3:1 basis. GPT-5.6 Luna accepts the larger context window (1.1M).
Head to head
Blended price uses a 3:1 input:output mix
| Gemini 3.5 Flash | GPT-5.6 Luna | |
|---|---|---|
| Provider | OpenAI | |
| Input $/1M | $1.50 | $0.100 |
| Output $/1M | $9.00 | $0.600 |
| Blended $/1M | $3.38 | $0.225 |
| Context window | 1.0M | 1.1M |
| Max output | 66K | 128K |
| Released | May 2026 | Jul 2026 |
| Licence | Proprietary | Proprietary |
| GPQA Diamond | 92.8% | 91.6% |
| FrontierMath T1–3 | 62.8% | 82.1% |
| FrontierMath T4 | 26.8% | 61.0% |
| SimpleQA Verified | 68.4% | 41.7% |
| OTIS Mock AIME | 95.6% | 98.3% |
Benchmark scores independently run and published by Epoch AI, 'AI Benchmarking Hub', used under CC BY 4.0. Only benchmarks with a score for BOTH models are compared.
Choose Gemini 3.5 Flash if…
- Higher GPQA Diamond (92.8% vs 91.6%)
- Higher SimpleQA Verified (68.4% vs 41.7%)
Choose GPT-5.6 Luna if…
- Costs less per token — $0.225 vs $3.38 blended
- Higher FrontierMath T1–3 (82.1% vs 62.8%)
- Higher FrontierMath T4 (61.0% vs 26.8%)
- Higher OTIS Mock AIME (98.3% vs 95.6%)
- Larger context window (1.1M)
- Newer model (released Jul 2026)
FAQ
Which is better, Gemini 3.5 Flash or GPT-5.6 Luna?
Across the 5 benchmarks both models have independently-run scores for, Gemini 3.5 Flash leads on 2 and GPT-5.6 Luna leads on 3. Benchmarks are one input — price and context window are on this page too.
Is Gemini 3.5 Flash cheaper than GPT-5.6 Luna?
GPT-5.6 Luna is cheaper: $0.225 versus $3.38 per million tokens blended at 3:1 input:output. Input alone: $1.50 vs $0.100. Output alone: $9.00 vs $0.600.
What context windows do Gemini 3.5 Flash and GPT-5.6 Luna have?
Gemini 3.5 Flash: 1,048,576 tokens. GPT-5.6 Luna: 1,050,000 tokens.
Who makes Gemini 3.5 Flash and GPT-5.6 Luna?
Gemini 3.5 Flash is made by Google. GPT-5.6 Luna is made by OpenAI.
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