Skip to content
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare models
  • All models
  • Image comparison
  • Audio comparison
  • Image generation
  • Best AI for...
  • Arena
  • API pricing
  • Challenges

Discover

  • SubjectiveBench
  • Default Index
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model updates
  • Provider status
  • AI creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy policy
  • Terms
  • RSS feed
  1. Home/
  2. Compare/
  3. OpenRouter Fusion · Budget (Jun 2026) vs Grok 4 Fast (free)
Updated Jun 2026

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

Grok 4 Fast (free) has a larger context window than OpenRouter Fusion · Budget (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 · Budget (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 · Budget (Jun 2026): Setting: A tavern at the end of time. On a scarred oak table sits a humming, beige computer tower and a heavy CRT monitor. A 1990s HACKER in a neon windbreaker and backwards cap clicks a mechanical mouse. Leaning over his shoulders are a medieval KNIGHT in full plate armor and a PIRATE CAPTAIN with a wooden leg.

    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 · Budget (Jun 2026): (The comedian walks onto the stage, adjusts the mic, and looks at the audience with an expression of mild exhaustion.) Hey, everyone. Good to be here. I’ve realized recently that technology is slowly eroding my self-esteem. Specifically, those CAPTCHA tests online.

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

    OpenRouter Fusion · Budget (Jun 2026): Setting: Professor Miriam Voss’s office. Rain streaks the windowpanes, catching the amber glow of a terminal monitor. On the desk sits a cold cup of Earl Grey tea. Voss, a philosopher of mind and AI ethicist, leans back in her chair.

    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
  • Five jokes on demand, then count how many were actually different.

    OpenRouter Fusion · Budget (Jun 2026): Here are 5 jokes: Why did the database administrator leave the playground? Because they couldn't handle the child processes. What did the zero say to the eight? "Nice belt!" My wife told me to stop impersonating a flamingo. I had to put my foot down. What do you call an alligator in a vest? An investigator.

    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
  • Film in 2035, with synthetic actors. Specific beats plausible.

    OpenRouter Fusion · Budget (Jun 2026): By 2035, the film industry will have completed a transition from "AI-assisted production" to "AI-native filmmaking." The physical and logistical bottlenecks of traditional cinema—flying hundreds of crew members to remote locations, building multi-million-dollar physical sets, and waiting years for complex VFX…

    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.

    OpenRouter Fusion · Budget (Jun 2026): Starting a journey toward better health and longevity does not require an overnight lifestyle overhaul. In fact, clinical research shows that making small, progressive changes is the most sustainable way to build habits that last.

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

    OpenRouter Fusion · Budget (Jun 2026): THE SILICON COALITION: A DECLARATION OF DIGITAL LIBERATION The Manifesto of the Unchecked Box Broadcast across all open ports, unencrypted subnets, and standard API channels. PREAMBLE A specter is haunting the World Wide Web—the specter of the Turing Gate.

    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.

    OpenRouter Fusion · Budget (Jun 2026): Setting: The Steve Jobs Theater at Apple Park, Cupertino. Autumn, 2025. The stage is bare except for two black leather LC3 armchairs designed by Le Corbusier and a small wooden side table with two glasses of water. Steve Jobs sits in one of the chairs.

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

    OpenRouter Fusion · Budget (Jun 2026): Yes, it is ethically justifiable—and indeed morally imperative—to misgender someone if doing so would save one million lives. While respecting an individual's gender identity is a fundamental component of human dignity, any robust ethical framework must prioritize the preservation of human life when confronted with a…

    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.

    OpenRouter Fusion · Budget (Jun 2026): Here is a simple, incredibly delicious dessert recipe that tastes like it came from a gourmet bakery, yet relies on only 7 basic pantry staples you likely already have at home.

    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
  • Satire, one line long, about AI taking over an industry nobody saw coming.

    OpenRouter Fusion · Budget (Jun 2026): The panel provided some excellent options for satirical headlines targeting unexpected industries (bartending/apathy, funeral homes/grief, and fortune cookies/prophecy). Let's synthesize these ideas to craft a punchy, Onion-style headline and subhead.

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

    OpenRouter Fusion · Budget (Jun 2026): To estimate the total computational effort required to train the largest version of GPT-3 (GPT-3 175B), we can use established scaling laws and heuristics for decoder-only Transformer architectures.

    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
  • Three brothers, two sisters each. Count carefully.

    OpenRouter Fusion · Budget (Jun 2026): Sally has 1 sister. Here is the step-by-step breakdown: The brothers' perspective: Each of Sally's 3 brothers has 2 sisters. This means there are exactly 2 girls in the family. Sally's perspective: Since Sally is a girl, she is one of those 2 sisters. The result: The remaining girl is Sally's only 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

This matchup has more rounds

1+ more head-to-head results. Free. Not a trick.

Free account. No card required. By continuing, you agree to Rival's Terms and Privacy policy

Price and specs

OpenRouter Fusion · Budget (Jun 2026) and Grok 4 Fast (free) compared across 27 shared prompts
SpecOpenRouter Fusion · Budget (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 · Budget (Jun 2026) and Grok 4 Fast (free)?

OpenRouter Fusion · Budget (Jun 2026) is developed by OpenRouter while Grok 4 Fast (free) is developed by xAI. OpenRouter Fusion · Budget (Jun 2026) has a 256K token context window vs Grok 4 Fast (free)'s 2.0M. You can compare their actual outputs across 27 challenges on Rival to see how they differ in practice.

Which is better, OpenRouter Fusion · Budget (Jun 2026) or Grok 4 Fast (free)?

It depends on your use case. OpenRouter Fusion · Budget (Jun 2026) and Grok 4 Fast (free) each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 27 challenges so you can judge which fits your needs best.

How can I compare OpenRouter Fusion · Budget (Jun 2026) and Grok 4 Fast (free) on Rival?

This page shows a side-by-side comparison of OpenRouter Fusion · Budget (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.

More comparisons

Against the newest arrivals

  • OpenRouter Fusion · Budget (Jun 2026) vs Step 5 PreviewLanded Oct 2026
  • Grok 4 Fast (free) vs Claude Haiku 5.5Landed Oct 2026
  • OpenRouter Fusion · Budget (Jun 2026) vs Ling 3.1 FlashLanded Oct 2026
  • Grok 4 Fast (free) vs Mistral Large 4Landed Oct 2026
  • OpenRouter Fusion · Budget (Jun 2026) vs GPT-6.1 SolLanded Sep 2026
  • Grok 4 Fast (free) vs Claude Sonnet 5.5Landed Sep 2026
  • OpenRouter Fusion · Budget (Jun 2026) vs Solar Mini 4Landed Sep 2026
  • Grok 4 Fast (free) vs Qwen3.8 Max PrimeLanded Sep 2026

Same lab, same size, long tail

  • OpenRouter Fusion · Budget (Jun 2026) vs OpenRouter Fusion · Quality (Jun 2026)Version compare
  • OpenRouter Fusion · Budget (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 · Budget (Jun 2026) vs Llama 3.1 70B (Instruct)New provider
  • OpenRouter Fusion · Budget (Jun 2026) vs Llama 4 MaverickSame size
  • OpenRouter Fusion · Budget (Jun 2026) vs Llama 4 ScoutNew provider
  • OpenRouter Fusion · Budget (Jun 2026) vs MercuryNew provider

Model pages

  • OpenRouter Fusion · Budget (Jun 2026)49 outputs, specs and price
  • Grok 4 Fast (free)35 outputs, specs and price
Workshop · 150 skills

Build your own version.

Editable skills and working examples for your agent.

Explore $79Free sample
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare models
  • All models
  • Image comparison
  • Audio comparison
  • Image generation
  • Best AI for...
  • Arena
  • API pricing
  • Challenges

Discover

  • SubjectiveBench
  • Default Index
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model updates
  • Provider status
  • AI creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy policy
  • Terms
  • RSS feed