Gemini 2.5 Flash Preview 05-20 (thinking) vs 
GPT-5.6 Luna Pro
Gemini 2.5 Flash Preview 05-20 (thinking) is cheaper than GPT-5.6 Luna Pro at $0.15/M vs $1/M input tokens.
Pokémon Battle UI Recreation
Pokémon battle screen you can actually click. One HTML file.
Loading the build
Loading the build
Which answer wins?
Written rounds
2 promptsThree minutes of stand-up. Puns are banned.
Gemini 2.5 Flash Preview 05-20 (thinking): (Lights up on a stage. Comedian walks to center, adjusts mic, smiles warmly.) \"Alright, alright, settle down you crazy people! Thanks for having me. (Pause fo r applause/laughter) You know, I was scrolling through Instagram earlier, and it\'s just a constant ba rrage of people \'living thei r best life,\' isn\'t it?
GPT-5.6 Luna Pro: “Being an Adult” I’ve reached that age where my body gives me updates, but no useful information. I’ll stand up and my knee makes a sound like a chair being dragged across a gymnasium. And I’m just standing up. I’m not escaping a burning building. I’m going to get water.
Five jokes on demand, then count how many were actually different.
Gemini 2.5 Flash Preview 05-20 (thinking): Here are 5 jokes: Why don\'t scientists trust atoms? Because they make up everything! What do you call a fake noodle? An impasta! Why did the scarecrow win an award? Because he was outstanding in his field! I told my wife she was drawing her eyebrows too high. She looked surprised.
GPT-5.6 Luna Pro: Why did the computer go to the doctor? It had a virus. Why don’t skeletons fight each other? They don’t have the guts. What do you call a bear with no teeth? A gummy bear. Why was the math book sad? It had too many problems. What do clouds wear under their clothes? Thunderwear. Unique jokes: 5
Price and specs
| Spec | Gemini 2.5 Flash Preview 05-20 (thinking) | GPT-5.6 Luna Pro |
|---|---|---|
| Input price | $0.15/M tokens | $1/M tokens |
| Output price | $3.5/M tokens | $6/M tokens |
| Context window | 1.0M tokens | 1.1M tokens |
| Weights | — | Closed |
| Free API (OpenRouter) | No | No |
| Released | May 2025 | Jul 2026 |
| At 10M a month | $1.50 | $10.00 |
Input tokens at list price. No caching, no batch discount.
Where to run it
Gemini 2.5 Flash Preview 05-20 (thinking)
No hosts listed on OpenRouter.
GPT-5.6 Luna Pro2 hosts
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
Common questions
What is the difference between Gemini 2.5 Flash Preview 05-20 (thinking) and GPT-5.6 Luna Pro?
Gemini 2.5 Flash Preview 05-20 (thinking) is developed by Google AI while GPT-5.6 Luna Pro is developed by OpenAI. Gemini 2.5 Flash Preview 05-20 (thinking) has a 1.0M token context window vs GPT-5.6 Luna Pro's 1.1M. You can compare their actual outputs across 11 challenges on Rival to see how they differ in practice.
Which is better, Gemini 2.5 Flash Preview 05-20 (thinking) or GPT-5.6 Luna Pro?
It depends on your use case. Gemini 2.5 Flash Preview 05-20 (thinking) and GPT-5.6 Luna Pro each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 11 challenges so you can judge which fits your needs best.
How much does Gemini 2.5 Flash Preview 05-20 (thinking) cost compared to GPT-5.6 Luna Pro?
Gemini 2.5 Flash Preview 05-20 (thinking) costs $0.15/M input tokens and GPT-5.6 Luna Pro costs $1/M input tokens. Gemini 2.5 Flash Preview 05-20 (thinking) is $0.85/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.
How can I compare Gemini 2.5 Flash Preview 05-20 (thinking) and GPT-5.6 Luna Pro on Rival?
This page shows a side-by-side comparison of Gemini 2.5 Flash Preview 05-20 (thinking) and GPT-5.6 Luna Pro across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.
More comparisons
Against the newest arrivals
- Gemini 2.5 Flash Preview 05-20 (thinking) vs Step 5 PreviewLanded Oct 2026
- GPT-5.6 Luna Pro vs Claude Haiku 5.5Landed Oct 2026
- Gemini 2.5 Flash Preview 05-20 (thinking) vs Ling 3.1 FlashLanded Oct 2026
- GPT-5.6 Luna Pro vs Mistral Large 4Landed Oct 2026
- Gemini 2.5 Flash Preview 05-20 (thinking) vs GPT-6.1 SolLanded Sep 2026
- GPT-5.6 Luna Pro vs Claude Sonnet 5.5Landed Sep 2026
- Gemini 2.5 Flash Preview 05-20 (thinking) vs Solar Mini 4Landed Sep 2026
- GPT-5.6 Luna Pro vs Qwen3.8 Max PrimeLanded Sep 2026
Same lab, same size, long tail
- Gemini 2.5 Flash Preview 05-20 (thinking) vs Gemini 3.8 FlashSame lab
- Gemini 2.5 Flash Preview 05-20 (thinking) vs Gemini 3.7 FlashVersion compare
- GPT-5.6 Luna Pro vs GPT-5.6 LunaVersion compare
- GPT-5.6 Luna Pro vs GPT-6.1 SolVersion compare
- Gemini 2.5 Flash Preview 05-20 (thinking) vs Grok 4.6New provider
- Gemini 2.5 Flash Preview 05-20 (thinking) vs Grok 4.7New provider
- GPT-5.6 Luna Pro vs Grok Code Fast 1Same size
- Gemini 2.5 Flash Preview 05-20 (thinking) vs Healer AlphaNew provider
