Claude Opus 5 vs 
Gemini 2.5 Flash Preview 05-20 (thinking)
Gemini 2.5 Flash Preview 05-20 (thinking) is cheaper than Claude Opus 5 at $0.15/M vs $5/M input tokens.
Pokémon Battle UI Recreation
Pokémon battle screen you can actually click. One HTML file.
Loading the build
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Which answer wins?
Written rounds
2 promptsThree minutes of stand-up. Puns are banned.
Claude Opus 5: "Warranty Expired" (approx. 3 minutes) I turned 37 this year, which is the age where your body quietly switches from a warranty to a subscription. Nothing's covered anymore. You just pay monthly, in pain, forever. Because I hurt my shoulder last week. Sleeping. I hurt myself sleeping.
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?
Five jokes on demand, then count how many were actually different.
Claude Opus 5: Here are five: Why don't skeletons ever fight each other? They don't have the guts. I told my wife she was drawing her eyebrows too high. She looked surprised. Parallel lines have so much in common. It's a shame they'll never meet. I bought some shoes off a drug dealer.
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.
Price and specs
Not enough votes to call it. On the specs, Claude Opus 5 has the edge: bigger model tier, newer. Gemini 2.5 Flash Preview 05-20 (thinking) costs 7.1x less per token.
| Spec | Claude Opus 5 | Gemini 2.5 Flash Preview 05-20 (thinking) |
|---|---|---|
| Input price | $5/M tokens | $0.15/M tokens |
| Output price | $25/M tokens | $3.5/M tokens |
| Context window | 1.0M tokens | 1.0M tokens |
| Weights | Closed | — |
| Free API (OpenRouter) | No | No |
| Released | Jul 2026 | May 2025 |
| At 10M a month | $50.00 | $1.50 |
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.
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
Common questions
What is the difference between Claude Opus 5 and Gemini 2.5 Flash Preview 05-20 (thinking)?
Claude Opus 5 is developed by Anthropic while Gemini 2.5 Flash Preview 05-20 (thinking) is developed by Google AI. Claude Opus 5 has a 1.0M token context window vs Gemini 2.5 Flash Preview 05-20 (thinking)'s 1.0M. You can compare their actual outputs across 11 challenges on Rival to see how they differ in practice.
Which is better, Claude Opus 5 or Gemini 2.5 Flash Preview 05-20 (thinking)?
It depends on your use case. Claude Opus 5 and Gemini 2.5 Flash Preview 05-20 (thinking) 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 Claude Opus 5 cost compared to Gemini 2.5 Flash Preview 05-20 (thinking)?
Claude Opus 5 costs $5/M input tokens and Gemini 2.5 Flash Preview 05-20 (thinking) costs $0.15/M input tokens. Gemini 2.5 Flash Preview 05-20 (thinking) is $4.85/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 Claude Opus 5 and Gemini 2.5 Flash Preview 05-20 (thinking) on Rival?
This page shows a side-by-side comparison of Claude Opus 5 and Gemini 2.5 Flash Preview 05-20 (thinking) 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.
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