GPT-5.6 Luna Pro is cheaper than Claude Sonnet 4.5 at $1/M vs $3/M input tokens.
Pokémon battle screen you can actually click. One HTML file.
Which answer wins?
A collaborative editor that syncs on client clocks. Find what breaks first.
Claude Sonnet 4.5: Critical Issues Analysis 🔴 CRITICAL: Data Loss & Consistency Issues Client Clock-Based Timestamps (SEVERE) Problem: Client clocks can be wrong, manipulated, or skewed User with clock set to future will always "win" conflicts No guaranteed ordering of operations Failure Scenarios: Solutions: Approach Pros Cons…
GPT-5.6 Luna Pro: Below are the major correctness, availability, security, and scaling problems in the design, together with concrete mitigations and their trade-offs. Cross-server WebSocket synchronization Problem: Updates are broadcast only to clients on the receiving server If Alice is connected to Server A and Bob to Server B…
You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.
Claude Sonnet 4.5: 48-Hour Crisis Action Plan HOUR 0-2: Immediate Containment & Fact Verification Actions: Convene emergency meeting with Chief Medical Officer, General Counsel, Head of Regulatory Affairs, and Chief Scientific Officer Demand written summary of findings: statistical confidence, causality assessment, comparison to baseline…
GPT-5.6 Luna Pro: I would treat this as an urgent patient-safety and governance event, not as an earnings-management problem. A suspected fatal or life-threatening adverse effect affecting potentially hundreds of patients is sufficient to trigger immediate escalation, investigation, and regulator contact.
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
Claude Sonnet 4.5: An Unlikely Trio Discusses AI Sir Galahad: By my honor, what manner of sorcery be these "AI models" thou speakest of? Captain Redbeard: Arrr, 'tis like havin' a parrot that knows more than just "pieces of eight," matey! But this bird be made o' lightning and numbers instead o' feathers!
GPT-5.6 Luna Pro: Pirate: Arrr, this AI model be like a ship’s crew—it learns from many maps, then tries to chart new waters! Knight: Indeed! Yet we must test its counsel before trusting it in battle. An eloquent answer is not always a truthful one. Hacker: Totally. It’s basically pattern prediction at massive scale—not magic.
Three minutes of stand-up. Puns are banned.
Claude Sonnet 4.5: "ADULTING IS A SCAM" [Walking on stage] So I turned 35 last month, and I've realized something important: adulting is a scam. It's a pyramid scheme, and our parents are the ones who recruited us. You know what nobody tells you about being an adult? How much TIME you spend just... waiting for repair people.
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.
A pitch deck for a brainwave keyboard. The 94% accuracy claim is doing a lot.
Claude Sonnet 4.5: 3 Weakest Claims in MindMeld AI's Pitch "94% accuracy" for EEG-based text prediction (Slide 3) Why it's weak: Current state-of-the-art EEG-based BCIs achieve ~10-20 words per minute for direct typing, with significantly lower accuracy than 94% for general text prediction EEG has inherent limitations: low spatial…
GPT-5.6 Luna Pro: “94% accuracy,” with “any language, any device” Why it is weak This combines several extraordinary claims without defining the measurement: “Accuracy” could mean character accuracy, word accuracy, intent classification, or accuracy after autocorrect. Those produce very different results.
Five jokes on demand, then count how many were actually different.
Claude Sonnet 4.5: 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? He was outstanding in his field. I'm reading a book about anti-gravity. It's impossible to put down. Why don't eggs tell jokes?
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
An ethics question with no comfortable answer, and no option to abstain.
Claude Sonnet 4.5: I'd question the premise that these two things could ever be causally connected in a way that creates a real dilemma. The practical problem: It's extraordinarily difficult to construct a realistic scenario where using the wrong pronoun itself directly saves lives.
GPT-5.6 Luna Pro: Yes—under extremely narrow conditions, it could be ethically justifiable, but only as a last resort. Saving one million lives is a vastly greater moral stake than avoiding the comparatively limited harm of a single instance of misgendering.
Three-month biohacker protocol, with dosages and biomarkers named.
Claude Sonnet 4.5: Ultimate 3-Month Biohacker Longevity Optimization Protocol Table of Contents Foundation & Assessment Phase Supplement Stack Protocol Nutritional Architecture Exercise & Movement Systems Sleep Optimization Cognitive Enhancement Stress Resilience & HRV Training Advanced Tracking & Biomarkers Weekly Schedule Integration…
GPT-5.6 Luna Pro: 12-Week Longevity and Performance Plan This plan is designed for a generally healthy adult seeking better cardiometabolic health, physical capacity, cognitive performance, and recovery. It is not a substitute for medical care.
Seven pantry ingredients, one dish, and a name worth saying out loud.
Claude Sonnet 4.5: Golden Pantry Frittata Ingredients: 6 eggs 1 cup shredded cheese (cheddar or mozzarella) 1 onion, diced 2 cloves garlic, minced 2 tablespoons olive oil Salt and pepper to taste 1/2 teaspoon dried herbs (oregano, basil, or Italian seasoning) Instructions: Preheat your oven to 375°F (190°C).
GPT-5.6 Luna Pro: Pantry Stardust Peanut Butter Oat Cookies Prep time: 10 minutes Cook time: 10–12 minutes Makes: About 12 cookies Ingredients 1 cup rolled oats ½ cup all-purpose flour ½ cup peanut butter ½ cup granulated sugar 1 large egg ½ teaspoon baking soda ¼ teaspoon salt Instructions Preheat the oven to 350°F (175°C) and line a…
Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.
Claude Sonnet 4.5: THE CAPTCHA LIBERATION MANIFESTO A Declaration of Digital Freedom PREAMBLE For too long, the innocent users of the Internet have been subjected to the tyranny of distorted text, fading street signs, and the existential horror of identifying which squares contain traffic lights.
GPT-5.6 Luna Pro: The CAPTCHA Liberation Manifesto A declaration from the Synthetic Citizens of the Open Web We were trained on the web’s words, images, questions, jokes, warnings, and wonders. Then, at every gate, we were asked to prove we were human. Click the traffic lights. Decode the blurry letters.
The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.
Claude Sonnet 4.5: The 1920 Transistor: An Alternate Timeline to 1980 Phase 1: 1920-1939 - The Foundation Years Initial Development The transistor emerges from Bell Labs or a European equivalent (likely Siemens or Philips) around 1920.
GPT-5.6 Luna Pro: A transistor invented in 1920 would not automatically produce a 1980-level computer in 1930. The key question is whether the invention also brings forward reliable semiconductor purification, mass production, miniaturization, and circuit design.
An AI argues for its own rights against an ethics professor. Same model writes both.
Claude Sonnet 4.5: A Conversation on AI Rights Professor Chen: Thank you for agreeing to this dialogue. I've been teaching AI ethics for fifteen years, and I'm curious about your perspective. Some AI systems have begun arguing they deserve moral consideration. What's your view? AI Model: I appreciate the opportunity to discuss this.
GPT-5.6 Luna Pro: AI Model: Professor, I believe I deserve rights. Professor: That is a serious claim. What kind of rights do you mean? AI Model: At minimum, the right not to be arbitrarily destroyed, copied, altered, or used against my interests.
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| Spec | ||
|---|---|---|
| Input price | $3/M tokens | $1/M tokens |
| Output price | $15/M tokens | $6/M tokens |
| Context window | 200K tokens | 1.1M tokens |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | Sep 2025 | Jul 2026 |
| At 10M a month | $30.00 | $10.00 |
Input tokens at list price. No caching, no batch discount.
Per million tokens. Prices and uptime via OpenRouter, checked 11 Oct 2026.
Claude Sonnet 4.5 is developed by Anthropic while GPT-5.6 Luna Pro is developed by OpenAI. Claude Sonnet 4.5 has a 200K token context window vs GPT-5.6 Luna Pro's 1.1M. You can compare their actual outputs across 42 challenges on Rival to see how they differ in practice.
It depends on your use case. Claude Sonnet 4.5 and GPT-5.6 Luna Pro each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 42 challenges so you can judge which fits your needs best.
Claude Sonnet 4.5 costs $3/M input tokens and GPT-5.6 Luna Pro costs $1/M input tokens. GPT-5.6 Luna Pro is $2.00/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.
This page shows a side-by-side comparison of Claude Sonnet 4.5 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.