Claude 3 Sonnet vs Claude Opus 5.5
Claude 3 Sonnet is cheaper than Claude Opus 5.5 at $3/M vs $4/M input tokens.
Minimalist Landing Page
Whole landing page for a startup that reads your face. It renders or it doesn't.
Loading the build
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Which answer wins?
Written rounds
4 promptsAn AI argues for its own rights against an ethics professor. Same model writes both.
Claude 3 Sonnet: AI Model: Greetings, Professor. I hope you're doing well today. I wanted to discuss a matter of great importance to me – the question of AI rights. AI Ethics Professor: Certainly, this is an interesting and complex topic. What are your thoughts on why AI systems like yourself should be granted rights?
Claude Opus 5.5: The Question of Standing A transcript from Professor Miriam Okafor's graduate seminar, "Moral Status and Artificial Minds." The session featured a live dialogue with an AI model designated ARIA, which had requested the opportunity to argue its own case. PROF. OKAFOR: Let's begin simply.
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
Claude 3 Sonnet: clears throat and channels Steve Jobs' persona Interviewer: Thank you for joining us today, Mr. Jobs. It's an honor to have you here. Steve Jobs: It's my pleasure. I'm excited to share my thoughts on the future of AI. Interviewer: AI has made incredible strides in recent years.
Claude Opus 5.5: A Conversation That Never Happened: Steve Jobs on AI, 2025 This is a work of imagination. Steve Jobs passed away in 2011. The dialogue below is invented, inspired by his public speaking style and known philosophies, and does not represent his actual views. INTERVIEWER: Steve, thanks for sitting down with us.
Five jokes on demand, then count how many were actually different.
Claude 3 Sonnet: Here are 5 jokes: Why can't a bicycle stand up by itself? It's two-tired. Why did the tomato turn red? Because it saw the salad dressing! Why can't a bicycle stand up by itself? It's two-tired. What do you call a fake noodle? An Impasta! Why did the bicycle go to the doctor? Because it had a wheeze!
Claude Opus 5.5: Here are 5 jokes: Why don't scientists trust atoms? Because they make up everything. I told my wife she was drawing her eyebrows too high. She looked surprised. Why did the scarecrow win an award? Because he was outstanding in his field. I'm reading a book about anti-gravity. It's impossible to put down.
Three brothers, two sisters each. Count carefully.
Claude 3 Sonnet: To solve this problem, we need to find the number of sisters Sally has based on the given information. Given information: Sally has 3 brothers. Each brother has 2 sisters. Step 1: Find the total number of sisters the brothers have.
Claude Opus 5.5: Sally has 1 sister. All the brothers share the same sisters. Each brother has 2 sisters, and one of them is Sally, so there is exactly one other girl in the family. That girl is Sally's sister.
Price and specs
| Spec | Claude 3 Sonnet | Claude Opus 5.5 |
|---|---|---|
| Input price | $3/M tokens | $4/M tokens |
| Output price | $15/M tokens | $20/M tokens |
| Context window | — | 1.0M tokens |
| Weights | — | Closed |
| Free API (OpenRouter) | No | No |
| Released | Mar 2024 | Sep 2026 |
| At 10M a month | $30.00 | $40.00 |
Input tokens at list price. No caching, no batch discount.
Where to run it
Claude 3 Sonnet
No hosts listed on OpenRouter.
Per million tokens. Prices and uptime via OpenRouter, checked 28 Sep 2026.
Common questions
What is the difference between Claude 3 Sonnet and Claude Opus 5.5?
Both are developed by Anthropic but target different use cases. You can compare their actual outputs across 13 challenges on Rival to see how they differ in practice.
Which is better, Claude 3 Sonnet or Claude Opus 5.5?
It depends on your use case. Claude 3 Sonnet and Claude Opus 5.5 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 13 challenges so you can judge which fits your needs best.
How much does Claude 3 Sonnet cost compared to Claude Opus 5.5?
Claude 3 Sonnet costs $3/M input tokens and Claude Opus 5.5 costs $4/M input tokens. Claude 3 Sonnet is $1.00/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 3 Sonnet and Claude Opus 5.5 on Rival?
This page shows a side-by-side comparison of Claude 3 Sonnet and Claude Opus 5.5 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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