Claude Sonnet 5.5 vs 
OpenAI Codex Mini
OpenAI Codex Mini is cheaper than Claude Sonnet 5.5 at $1.5/M vs $2/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 promptsFive jokes on demand, then count how many were actually different.
Claude Sonnet 5.5: Here are 5 jokes: Why don't scientists trust atoms? Because they make up everything. I told my computer I needed a break, and now it won't stop sending me vacation ads. Why did the scarecrow win an award? He was outstanding in his field. What do you call a fish with no eyes? A fsh. Why did the bicycle fall over?
OpenAI Codex Mini: Sure—here are five jokes: I asked the librarian if books about paranoia were available. She whispered, "They're right behind you." Why did the tomato turn red? Because it saw the salad dressing. I bought a boat because it was for sail. Don't trust stairs—they're always up to something.
Three minutes of stand-up. Puns are banned.
Claude Sonnet 5.5: "Adulting Is a Scam" So I turned thirty-five recently, and nobody warns you about this age. Nobody says, "Hey, one day you'll get excited about a sponge." I was in the store, and I saw a sponge that promised it wouldn't smell. And I thought, "Finally. Someone who understands me." I bought the good sponge.
OpenAI Codex Mini: [Comedian walks onstage] Hey, everyone! Great to see you all tonight. I'm Jamie—if you thought that intro was enthusiastic, you should've seen me when I realized this place has Wi-Fi. Seriously, though, I love stand-up.
Price and specs
Not enough votes to call it. On the specs, Claude Sonnet 5.5 has the edge: bigger model tier, newer, bigger context window.
| Spec | Claude Sonnet 5.5 | OpenAI Codex Mini |
|---|---|---|
| Input price | $2/M tokens | $1.5/M tokens |
| Output price | $10/M tokens | $6/M tokens |
| Context window | 1.0M tokens | 200K tokens |
| Weights | Closed | — |
| Free API (OpenRouter) | No | No |
| Released | Sep 2026 | May 2025 |
| At 10M a month | $20.00 | $15.00 |
Input tokens at list price. No caching, no batch discount.
Where to run it
OpenAI Codex Mini
No hosts listed on OpenRouter.
Per million tokens. Prices and uptime via OpenRouter, checked 29 Sep 2026.
Common questions
What is the difference between Claude Sonnet 5.5 and OpenAI Codex Mini?
Claude Sonnet 5.5 is developed by Anthropic while OpenAI Codex Mini is developed by OpenAI. Claude Sonnet 5.5 has a 1.0M token context window vs OpenAI Codex Mini's 200K. You can compare their actual outputs across 10 challenges on Rival to see how they differ in practice.
Which is better, Claude Sonnet 5.5 or OpenAI Codex Mini?
It depends on your use case. Claude Sonnet 5.5 and OpenAI Codex Mini each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 10 challenges so you can judge which fits your needs best.
How much does Claude Sonnet 5.5 cost compared to OpenAI Codex Mini?
Claude Sonnet 5.5 costs $2/M input tokens and OpenAI Codex Mini costs $1.5/M input tokens. OpenAI Codex Mini is $0.50/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 Sonnet 5.5 and OpenAI Codex Mini on Rival?
This page shows a side-by-side comparison of Claude Sonnet 5.5 and OpenAI Codex Mini 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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