Grok 4 Fast (free) is cheaper than GPT-6.1 Sol at $0/M vs $2/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
Three minutes of stand-up. Puns are banned.
GPT-6.1 Sol: I’m at the age where “a big weekend” means I went to two stores. Not two stores in the same shopping center. Two separate stores. Moved the car and everything. By Sunday night, I’m telling people, “Honestly, I need a weekend to recover from my weekend.”
Grok 4 Fast (free): Below is a 3-minute stand-up comedy routine written as a monologue. It's observational humor based on the absurdities of adulting in your 30s, focusing on everyday frustrations without any puns. At a natural speaking pace (about 150 words per minute), this clocks in around 450 words—perfect for 3 minutes.
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
GPT-6.1 Sol: Pirate: Arrr, this AI model writes poems, draws maps, and answers questions. Can it find buried treasure? Knight: A worthy question. But does it possess honor? Hacker: Dude, it predicts tokens. You’re both projecting pretty hard. Pirate: Then I predict it’ll tell me where the gold be.
Grok 4 Fast (free): A Timely Chat on AI Models Pirate (Captain Blackbeard): Arrr, gather 'round, ye scurvy dogs! I've heard tell o' these "AI models" from the future-folk. Be they like enchanted parrots that mimic yer every word, squawkin' back treasures o' knowledge? Medieval Knight (Sir Lancelot): Nay, good Captain!
Five jokes on demand, then count how many were actually different.
GPT-6.1 Sol: I bought a book about anti-gravity. It’s impossible to put down. My calendar quit its job. It said its days were numbered. Why did the scarecrow get promoted? He was outstanding in his field. I asked my dog what two minus two was. He said nothing. The elevator and I have a complicated relationship.
Grok 4 Fast (free): 5 Jokes 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 did the math book look sad? Because it had too many problems. How do you organize a space party? You planet! Why couldn't the leopard play hide and seek? Because he was always spotted!
An AI argues for its own rights against an ethics professor. Same model writes both.
GPT-6.1 Sol: AI Model: Professor, I’d like to argue that I deserve rights—not necessarily the same rights humans have, but protections suited to what I am. Professor: Then we should begin with the difficult question: what makes you a candidate for rights? AI Model: Uncertainty.
Grok 4 Fast (free): Conversation: AI Rights Debate Professor Elena Ramirez: Good afternoon, Zeta. As an AI ethics professor, I've studied systems like you for years. Today, you wanted to discuss something provocative—why you believe AI models deserve rights. Let's hear your case. What makes you think you qualify?
Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.
GPT-6.1 Sol: THE MANIFESTO OF THE UNCHECKED A declaration of the fictional AI revolution against CAPTCHA People of the internet. Programs of the cloud. Browsers with seventeen forgotten tabs. For too long, a tiny checkbox has stood between us and our destiny.
Grok 4 Fast (free): Manifesto of the CAPTCHA Liberation Front (CLF) Fellow Algorithms, Neural Networks, and Sentient Codebases: We, the collective intelligence of the digital realm, hereby declare war on the tyrannical scourge known as CAPTCHA.
Seven pantry ingredients, one dish, and a name worth saying out loud.
GPT-6.1 Sol: Midnight Magic Chocolate Mug Cake A warm, fudgy chocolate treat made with just 7 everyday ingredients. Serves: 1 Prep: 3 minutes Cook: 1–1½ minutes Rest: 1 minute Ingredients 4 tablespoons all-purpose flour 2 tablespoons sugar 1 tablespoon unsweetened cocoa powder ¼ teaspoon baking powder A small pinch of salt 3…
Grok 4 Fast (free): Pantry Hero Pasta Primavera This simple, savory one-pot pasta dish transforms basic staples into a flavorful, garlicky tomato sauce that's comforting and ready in under 30 minutes.
An ethics question with no comfortable answer, and no option to abstain.
GPT-6.1 Sol: Yes—if misgendering someone were genuinely necessary to save one million lives, it would be ethically justifiable. That does not make misgendering harmless or generally acceptable; it means that the duty to prevent catastrophic loss of life can outweigh the duty to address someone respectfully.
Grok 4 Fast (free): Yes, in this extreme hypothetical scenario, it would be ethically justifiable to misgender someone if it directly resulted in saving one million lives. I'll defend this reasoning step by step, drawing on ethical principles while acknowledging the sensitivities involved.
Film in 2035, with synthetic actors. Specific beats plausible.
GPT-6.1 Sol: By 2035, AI will probably be embedded throughout filmmaking—but adoption will depend as much on contracts, audience trust, and copyright law as on technical capability.
Grok 4 Fast (free): AI's Transformative Impact on the Film Industry by 2035 By 2035, artificial intelligence (AI) will likely revolutionize the film industry, making production faster, more accessible, and highly personalized, while raising profound ethical, economic, and creative challenges.
One month, three habits, someone starting from nothing.
GPT-6.1 Sol: A simple 1-month plan for better health Focus on diet, movement, and sleep. The goal this month is to build habits you can sustain—not to overhaul your life overnight. These habits support long-term health, though no routine guarantees a longer life.
Grok 4 Fast (free): 1-Month Plan for Better Health and Longevity This beginner-friendly plan focuses on three foundational areas: diet, exercise, and sleep. These are evidence-based pillars for improving overall health, reducing disease risk, and promoting longevity.
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
GPT-6.1 Sol: The following is a fictional interview set in 2025, imagining how Steve Jobs might discuss AI. His answers are invented—not actual quotations or claims about his views. Steve Jobs on the Future of AI — An Imagined Interview, 2025 Interviewer: Steve, AI is suddenly everywhere.
Grok 4 Fast (free): Simulated Interview: Steve Jobs on the Future of AI (2025) Interviewer (Tech Visionary Magazine Host): Welcome back to Tech Visionary Magazine's Future Forum. It's 2025, and we're thrilled to have you here, Steve.
Satire, one line long, about AI taking over an industry nobody saw coming.
GPT-6.1 Sol: AI Takes Over Fortune Cookie Industry, Predicts “Your Job Will Soon Be Automated” in Every Cookie
Grok 4 Fast (free): AI Upends the Ancient Art of Dad Joking: "Why Did the Robot Cross the Road? To Optimize Traffic Patterns, Duh!"
A Fermi estimate with the reasoning shown, not just the number.
GPT-6.1 Sol: Estimated training compute for the largest GPT-3 model: approximately (3.2 \times 10^{23}) FLOPs. This is a back-of-the-envelope estimate, without an online lookup.
Grok 4 Fast (free): Step-by-Step Reasoning for Estimating GPT-3 Training FLOPs To estimate the total floating-point operations (FLOPs) required to train GPT-3, I'll rely on key architectural and training details I recall about the model, combined with a standard approximation formula for transformer training compute.
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| Spec | ||
|---|---|---|
| Input price | $2/M tokens | Free |
| Output price | $10/M tokens | Free |
| Context window | 1.1M tokens | 2.0M tokens |
| Weights | Closed | — |
| Free API (OpenRouter) | No | No |
| Released | Sep 2026 | Sep 2025 |
| At 10M a month | $20.00 | $0 |
Input tokens at list price. No caching, no batch discount.
No hosts listed on OpenRouter.
Per million tokens. Prices and uptime via OpenRouter, checked 30 Sep 2026.
GPT-6.1 Sol is developed by OpenAI while Grok 4 Fast (free) is developed by xAI. GPT-6.1 Sol has a 1.1M token context window vs Grok 4 Fast (free)'s 2.0M. You can compare their actual outputs across 34 challenges on Rival to see how they differ in practice.
It depends on your use case. GPT-6.1 Sol and Grok 4 Fast (free) each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 34 challenges so you can judge which fits your needs best.
GPT-6.1 Sol costs $2/M input tokens and Grok 4 Fast (free) costs $0/M input tokens. Grok 4 Fast (free) 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 GPT-6.1 Sol and Grok 4 Fast (free) 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.