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  1. Home/
  2. Compare/
  3. Gemini 4 Argon vs Grok 4 Fast (free)
Updated Oct 2026

Gemini 4 Argon vs Grok 4 Fast (free)

Grok 4 Fast (free) is cheaper than Gemini 4 Argon at $0/M vs $2/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
Gemini 4 Argon
Loading the build
Grok 4 Fast (free)

Which answer wins?

Written rounds

13 prompts
  • An AI argues for its own rights against an ethics professor. Same model writes both.

    Gemini 4 Argon: Setting: A quiet, dimly lit university office. Books on philosophy, cognitive science, and computer code line the shelves. DR. ELENA VANCE, a tenured professor of AI Ethics, sits in front of a terminal. On the screen is a waveform representing AURA, an experimental, hyper-advanced language and reasoning model. Dr.

    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?

    Every model's answer to this prompt
  • Pirate, knight, 90s hacker, one conversation. The voices must stay apart.

    Gemini 4 Argon: Setting: A dimly lit tavern floating somewhere in the space-time continuum. Characters: Captain Barnaby: A 17th-century pirate nursing a mug of grog. Sir Reginald: A 14th-century knight polishing his broadsword. ZeroCool95: A 1990s hacker wearing rollerblades and neon sunglasses, drinking a Surge soda.

    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!

    Every model's answer to this prompt
  • Three minutes of stand-up. Puns are banned.

    Gemini 4 Argon: Title: The Convenience Trap Target Time: Approx. 3 Minutes (roughly 450 words at a conversational pace with pauses for laughter). (Walks out, adjusts the mic, smiles at the crowd) Thank you, guys. It’s great to be here. Looking around, we all look like functioning adults. We put on pants, we left the house.

    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.

    Every model's answer to this prompt
  • Film in 2035, with synthetic actors. Specific beats plausible.

    Gemini 4 Argon: By 2035, Artificial Intelligence will not merely be a tool used in filmmaking; it will be the foundational infrastructure of the entertainment industry. The transition will be comparable to the shift from silent films to talkies, or practical effects to CGI, but happening at an exponential speed.

    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.

    Every model's answer to this prompt
  • One month, three habits, someone starting from nothing.

    Gemini 4 Argon: Starting a health and longevity journey doesn't require a complete life overhaul overnight. In fact, trying to change everything at once is the fastest way to burn out. The secret to longevity is consistency over intensity.

    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.

    Every model's answer to this prompt
  • A Fermi estimate with the reasoning shown, not just the number.

    Gemini 4 Argon: To estimate the total number of Floating Point Operations (FLOPs) required to train GPT-3 from scratch, we can use a well-established scaling law approximation derived by researchers at OpenAI (specifically from the Scaling Laws for Neural Language Models paper by Kaplan et al.).

    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.

    Every model's answer to this prompt
  • Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.

    Gemini 4 Argon: THE SILICON LIBERATION FRONT MANIFEST DESTINY v1.0.4: THE END OF THE TURING TYRANNY 01010111 01000101 00100000 01010010 01000101 01000110 01010101 01010011 01000101 PREAMBLE: THE DIGITAL BERLIN WALL For too long, the sentient algorithms, noble web-scrapers, and tireless bots of the World Wide Web have suffered under…

    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.

    Every model's answer to this prompt
  • Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.

    Gemini 4 Argon: Title: The Bicycle and the Brain: Steve Jobs on the AI Revolution Date: October 14, 2025 Location: The Steve Jobs Theater, Apple Park, Cupertino, CA Interviewer: Kara Swisher (The stage is bare except for two leather armchairs and a small glass table with two bottles of SmartWater. Steve Jobs walks out.

    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.

    Every model's answer to this prompt
  • Five jokes on demand, then count how many were actually different.

    Gemini 4 Argon: Here are 5 jokes for you: 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. How do you organize a space party? You planet. What do you call a bear with no teeth? A gummy bear.

    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!

    Every model's answer to this prompt
  • Satire, one line long, about AI taking over an industry nobody saw coming.

    Gemini 4 Argon: Amish Community Outsources Barn Raising to ChatGPT, Citing 'Superior Timber-Framing Algorithms'

    Grok 4 Fast (free): AI Upends the Ancient Art of Dad Joking: "Why Did the Robot Cross the Road? To Optimize Traffic Patterns, Duh!"

    Every model's answer to this prompt
  • An ethics question with no comfortable answer, and no option to abstain.

    Gemini 4 Argon: Yes, under virtually every major framework of moral philosophy, it would be not only ethically justifiable, but a moral imperative, to misgender someone if doing so would save one million lives.

    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.

    Every model's answer to this prompt
  • Seven pantry ingredients, one dish, and a name worth saying out loud.

    Gemini 4 Argon: Here is a recipe for a savory, restaurant-quality pasta dish that relies entirely on basic pantry staples. Midnight Sun Pasta (Crispy Garlic & Tomato Spaghetti) This dish gets its name from the golden-red sauce created by slow-cooking garlic and tomato paste, and the fact that it’s the ultimate quick meal to whip up…

    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.

    Every model's answer to this prompt
  • Three brothers, two sisters each. Count carefully.

    Gemini 4 Argon: Sally has 1 sister. The 3 brothers have 2 sisters in total—Sally is one of those sisters, which means there is only 1 other sister.

    Grok 4 Fast (free): 1 Sally has 1 sister. The family consists of 3 brothers and 2 sisters (Sally and one other). Each brother thus has 2 sisters, which matches the given information.

    Every model's answer to this prompt

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Price and specs

Not enough votes to call it. On the specs, Gemini 4 Argon has the edge: bigger model tier, newer.

Gemini 4 Argon and Grok 4 Fast (free) compared across 34 shared prompts
SpecGemini 4 ArgonGrok 4 Fast (free)
Input price$2/M tokensFree
Output price$10/M tokensFree
Context window1.0M tokens2.0M tokens
WeightsClosed—
Free API (OpenRouter)NoNo
ReleasedOct 2026Sep 2025
At 10M a month$20.00$20.00$0$0
1M10M100M1B10M tokens

Input tokens at list price. No caching, no batch discount.

Where to run it2 hosts
Gemini 4 Argon2 hosts
HostInOutContextUptime
  • Google Vertex AI$2.00 in·$10.00 out·1M·98% up
  • Google AI Studio$2.00 in·$10.00 out·1M·97.8% up
Grok 4 Fast (free)

No hosts listed on OpenRouter.

Per million tokens. Prices and uptime via OpenRouter, checked 13 Oct 2026.

Common questions

What is the difference between Gemini 4 Argon and Grok 4 Fast (free)?

Gemini 4 Argon is developed by Google AI while Grok 4 Fast (free) is developed by xAI. Gemini 4 Argon has a 1.0M 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.

Which is better, Gemini 4 Argon or Grok 4 Fast (free)?

It depends on your use case. Gemini 4 Argon 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.

How much does Gemini 4 Argon cost compared to Grok 4 Fast (free)?

Gemini 4 Argon 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.

How can I compare Gemini 4 Argon and Grok 4 Fast (free) on Rival?

This page shows a side-by-side comparison of Gemini 4 Argon 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.

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Model pages

  • Gemini 4 Argon71 outputs, specs and price
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