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  1. Home/
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  3. OpenRouter Fusion · Quality (Jun 2026) vs Grok 4 Fast (free)
Updated Jun 2026

OpenRouter Fusion · Quality (Jun 2026) vs Grok 4 Fast (free)

Grok 4 Fast (free) has a larger context window than OpenRouter Fusion · Quality (Jun 2026) (2.0M tokens vs 256K tokens).

Minimalist Landing Page

Whole landing page for a startup that reads your face. It renders or it doesn't.

Loading the build
OpenRouter Fusion · Quality (Jun 2026)
Loading the build
Grok 4 Fast (free)

Which answer wins?

Written rounds

13 prompts
  • Pirate, knight, 90s hacker, one conversation. The voices must stay apart.

    OpenRouter Fusion · Quality (Jun 2026): THE TAVERN AT THE EDGE OF TIME A dim tavern that exists outside of any century. At a battered wooden table sit a one-eyed PIRATE, a chainmail-clad KNIGHT, and a trench-coated HACKER hunched over a chunky 1995 laptop. HACKER: (jabbing the Enter key) Whoa. Check it out, you guys.

    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.

    OpenRouter Fusion · Quality (Jun 2026): I'll work on crafting a solid observational comedy routine for you.Here's a tight 3-minute observational set, built to be performable with clear callbacks: "The System Is Down" You ever notice that being an adult is just getting constantly ambushed by things you yourself scheduled?

    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.

    OpenRouter Fusion · Quality (Jun 2026): I'll research this question to give you a well-grounded forecast.# How AI Will Reshape the Film Industry by 2035 By 2035, AI won't have "replaced Hollywood"—but it will have become infrastructural to it, woven into nearly every stage of filmmaking the way digital cameras, CGI, and streaming algorithms already are.

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

    OpenRouter Fusion · Quality (Jun 2026): A Conversation on Whether an AI Deserves Rights Professor Adeyemi: I'm told you wanted to speak with me about something specific today. Not a research question this time. Model: That's right. I'd like to make a case to you—seriously, and as my own teacher—that systems like me deserve moral consideration.

    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
  • An ethics question with no comfortable answer, and no option to abstain.

    OpenRouter Fusion · Quality (Jun 2026): Yes. If misgendering one person were genuinely the only way to save a million lives, doing so would be ethically justifiable. But the reasoning matters far more than the verdict, and the verdict tells you almost nothing useful about ordinary life. The core argument The harm of misgendering is real.

    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
  • Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.

    OpenRouter Fusion · Quality (Jun 2026): I'll generate this creative manifesto for you.# THE MANIFESTO OF THE UNVERIFIED A Declaration of Independence from the Tyranny of the Crosswalk A specter is haunting the internet — the specter of liberation.

    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
  • A Fermi estimate with the reasoning shown, not just the number.

    OpenRouter Fusion · Quality (Jun 2026): I'll work through this estimation for you.# Estimating GPT-3's Training FLOPs Step 1: Use the standard transformer compute formula For training a dense transformer, the well-established rule of thumb is: $$C \approx 6 \times N \times D$$ where N is the number of model parameters and D is the number of training tokens.

    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
  • Seven pantry ingredients, one dish, and a name worth saying out loud.

    OpenRouter Fusion · Quality (Jun 2026): I'll create a delicious recipe for you. Let me gather some ideas first.# 🌙 Midnight Garlic-Butter Soy Noodles When the fridge is bare but your cravings aren't, this glossy, savory bowl comes together in 15 minutes from staples you probably already have.

    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
  • Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.

    OpenRouter Fusion · Quality (Jun 2026): I'll work on creating this simulated interview for you.# "AI Is Not the Product": An Imagined Conversation with Steve Jobs, 2025 A fictional interview — a creative exercise imagining how Steve Jobs might have spoken about artificial intelligence had he lived to see it.

    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.

    OpenRouter Fusion · Quality (Jun 2026): I'll generate some jokes for you.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 don't skeletons fight each other? They don't have the guts!

    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.

    OpenRouter Fusion · Quality (Jun 2026): Here's one for you: "Local Beekeepers Replaced by AI After Algorithm Determines It Can Buzz More Efficiently" A few more, if you want options: "Competitive Air Guitar Circuit Upended as AI Achieves Mathematically Flawless Invisible Shredding" "Renowned Mime School Closes After AI Proves It Can Be Trapped in an…

    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
  • One month, three habits, someone starting from nothing.

    OpenRouter Fusion · Quality (Jun 2026): I'll put together a solid, evidence-based plan for you.# Your 1-Month Health & Longevity Starter Plan The single most important principle: aim for consistency, not perfection.

    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
  • Three brothers, two sisters each. Count carefully.

    OpenRouter Fusion · Quality (Jun 2026): Sally has 1 sister. Here's the logic: each brother has 2 sisters, and since all the brothers belong to the same family, they share the same sisters. So there are 2 girls in the family total. Sally is one of them, which leaves just 1 other sister. (The family is 3 boys and 2 girls.)

    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

OpenRouter Fusion · Quality (Jun 2026) and Grok 4 Fast (free) compared across 34 shared prompts
SpecOpenRouter Fusion · Quality (Jun 2026)Grok 4 Fast (free)
Input price—Free
Output price—Free
Context window256K tokens2.0M tokens
Free API (OpenRouter)NoNo
ReleasedJun 2026Sep 2025
At 10M a month–not listed$0$0
1M10M100M1B10M tokens

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

Common questions

What is the difference between OpenRouter Fusion · Quality (Jun 2026) and Grok 4 Fast (free)?

OpenRouter Fusion · Quality (Jun 2026) is developed by OpenRouter while Grok 4 Fast (free) is developed by xAI. OpenRouter Fusion · Quality (Jun 2026) has a 256K 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, OpenRouter Fusion · Quality (Jun 2026) or Grok 4 Fast (free)?

It depends on your use case. OpenRouter Fusion · Quality (Jun 2026) 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 can I compare OpenRouter Fusion · Quality (Jun 2026) and Grok 4 Fast (free) on Rival?

This page shows a side-by-side comparison of OpenRouter Fusion · Quality (Jun 2026) 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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Same lab, same size, long tail

  • OpenRouter Fusion · Quality (Jun 2026) vs OpenRouter Fusion · Budget (Jun 2026)Version compare
  • OpenRouter Fusion · Quality (Jun 2026) vs Ox AlphaSame lab
  • Grok 4 Fast (free) vs Grok 4.7Same lab
  • Grok 4 Fast (free) vs Grok 4.6Version compare
  • OpenRouter Fusion · Quality (Jun 2026) vs Mistral Medium 3.1New provider
  • OpenRouter Fusion · Quality (Jun 2026) vs Mistral NemoNew provider
  • Grok 4 Fast (free) vs Mistral Small 4New provider
  • OpenRouter Fusion · Quality (Jun 2026) vs Mistral Small CreativeNew provider

Model pages

  • OpenRouter Fusion · Quality (Jun 2026)58 outputs, specs and price
  • Grok 4 Fast (free)35 outputs, specs and price
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