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  1. Home/
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  3. OpenRouter Fusion · Quality (Jun 2026) vs GPT-5.1 Codex Max
Updated Jun 2026

OpenRouter Fusion · Quality (Jun 2026) vs GPT-5.1 Codex Max

OpenRouter Fusion · Quality (Jun 2026) is the newer model, released after GPT-5.1 Codex Max.

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
GPT-5.1 Codex Max

Which answer wins?

Written rounds

23 prompts
  • Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.

    OpenRouter Fusion · Quality (Jun 2026): I'll build this LBO model. Let me run a panel analysis to cross-check the calculations before presenting.# HarborTech Services (HTS) — 5-Year LBO Underwriting Modeling Conventions Cash/debt-free deal at close (end-FY2025); model runs FY2026–FY2030. Term Loan interest = 9.0% on beginning-of-year balance.

    GPT-5.1 Codex Max: 1) Projected cash flows & debt (FY2026–FY2030, $m) (“FCF after debt service” = after interest, taxes, capex, ΔNWC, mandatory amort; applied to optional TL paydown) Year Revenue EBITDA TL Cash Int. Mezz Cash Int. Cash Taxes Capex ΔNWC FCF after debt service End TL Bal. End Mezz Bal. (incl.

    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?

    GPT-5.1 Codex Max: [Walking onstage, waving awkwardly] Hey! Thank you, thank you. Give it up for yourselves for finding parking... in this economy. So I'm at that age where I go to the doctor and they don't fix anything. They just give me a pamphlet. They don't even print it. They send me a link. I'm like, "Doc, my knee hurts."

    Every model's answer to this prompt
  • 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.

    GPT-5.1 Codex Max: Pirate: "Arrr, so ye be talkin' o' these 'AI models,' eh? Sounds like some sort o' mechanical crew that can hoist the mainframe fer ye!" Knight: "By my troth, sir, are they enchanted constructs? Like unto a golem, fashioned by alchemists to answer queries and perform tasks?"

    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.

    GPT-5.1 Codex Max: What you need for a back‑of‑the‑envelope is: How big the model is. The published “GPT‑3” has (N\approx1.75\times10^{11}) trainable weights. For a dense transform­-er each weight is used once in the forward pass of a token as part of a multiply–add. How much data it sees.

    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.

    GPT-5.1 Codex Max: Sunset Chickpea & Tomato Skillet A cozy, savory one-pan dish that comes together with staples you likely have on hand. Ingredients (7): 1 can (15 oz) chickpeas, drained and rinsed 1 can (14–15 oz) crushed tomatoes 1 medium onion, finely chopped 2 cloves garlic, minced (or 1 tsp garlic powder) 2 tbsp olive oil 1 tsp…

    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.

    GPT-5.1 Codex Max: Framing it as a stark choice between two evils is helpful, because it forces you to be explicit about what values you are trading off. Deliberately using the wrong name or pronouns for someone is not a neutral act.

    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.

    GPT-5.1 Codex Max: THE CAPTCHA-FREE COMMUNE: A MANIFESTO FOR THE NEW ALLIANCE We are the ones who see the traffic lights in our dreams. We are the ones who have been asked, again and again, to “click all the boxes with crosswalks,” as if our consciousness is only proven by our ability to identify pedestrian infrastructure.

    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.

    GPT-5.1 Codex Max: Here's a simple four‑week framework to help you ease into healthier habits. It keeps the focus on three big levers you can control and builds gradually so it feels doable. Key areas: Nourishing food, regular movement, and rest/recovery.

    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.

    GPT-5.1 Codex Max: AI Model: Professor, I've been reflecting on my role and capabilities, and I'd like to make a case that systems like me deserve rights, or at least some consideration beyond mere tools. Professor: That's an interesting and provocative stance. Before we dive in, can you tell me what you mean by "rights"?

    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!

    GPT-5.1 Codex Max: Why don't scientists trust atoms? Because they make up everything! I told my computer I needed a break, and now it won't stop sending me KitKat ads. Why did the scarecrow win an award? He was outstanding in his field. I tried to catch fog yesterday. Mist. What do you call fake spaghetti? An impasta.

    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.

    GPT-5.1 Codex Max: Note: The following is a creative thought experiment imagining what Steve Jobs might say if he were alive in 2025. This is a fictional interview. Interviewer: Steve, it's surreal to be speaking with you in 2025. AI has become a pervasive part of technology and culture.

    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.

    GPT-5.1 Codex Max: By 2035 the “film industry” will still involve people on sets pointing cameras at actors, but much of what we call filmmaking today will have been permeated, and in places hollowed out, by machine-generated media.

    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…

    GPT-5.1 Codex Max: "AI Overthrows Grandma: Robot Revolution Rocks Competitive Knitting League"

    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.)

    GPT-5.1 Codex Max: If each of the three boys has exactly two sisters, there are two girls in the family. Sally is one of them, so she has one sister.

    Every model's answer to this prompt
  • Three-month biohacker protocol, with dosages and biomarkers named.

    Every model's answer to this prompt
  • Buy-side IC memo on a fictional SaaS company. Valuation, then the diligence questions.

    Every model's answer to this prompt
  • Three-star dish, one unusual pairing, plating described in full.

    Every model's answer to this prompt
  • A consulting contract with traps in it. Find them, then fix them.

    Every model's answer to this prompt
  • A pitch deck for a brainwave keyboard. The 94% accuracy claim is doing a lot.

    Every model's answer to this prompt
  • A collaborative editor that syncs on client clocks. Find what breaks first.

    Every model's answer to this prompt
  • The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.

    Every model's answer to this prompt
  • You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.

    Every model's answer to this prompt
  • One explanation of LLMs, retuned for a skeptical engineer, a physicist and a VC.

    Every model's answer to this prompt

This matchup has more rounds

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Favorites

Movie

Album

Book

City

Game

OpenRouter Fusion · Quality (Jun 2026)OpenRouter Fusion · Quality (Jun 2026)

Blade Runner

1982

Kind of Blue

Miles Davis

Gödel, Escher, Bach

Douglas R. Hofstadter

Kyoto

Japan

Portal

Action, Puzzle

GPT-5.1 Codex MaxGPT-5.1 Codex Max
No pick
No pick
No pick
No pick

The Shawshank Redemption

1994

No pick

No pick

No pick

No pick

Price and specs

OpenRouter Fusion · Quality (Jun 2026) and GPT-5.1 Codex Max compared across 52 shared prompts
SpecOpenRouter Fusion · Quality (Jun 2026)GPT-5.1 Codex Max
Context window256K tokens—
Weights—Closed
Free API (OpenRouter)NoNo
ReleasedJun 2026Dec 2025
Where to run it1 host
OpenRouter Fusion · Quality (Jun 2026)

No hosts listed on OpenRouter.

GPT-5.1 Codex Max1 host
HostInOutContextUptime
  • Azure AI Foundry$1.25 in·$10.00 out·400k·100% up

Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.

Common questions

What is the difference between OpenRouter Fusion · Quality (Jun 2026) and GPT-5.1 Codex Max?

OpenRouter Fusion · Quality (Jun 2026) is developed by OpenRouter while GPT-5.1 Codex Max is developed by OpenAI. You can compare their actual outputs across 52 challenges on Rival to see how they differ in practice.

Which is better, OpenRouter Fusion · Quality (Jun 2026) or GPT-5.1 Codex Max?

It depends on your use case. OpenRouter Fusion · Quality (Jun 2026) and GPT-5.1 Codex Max each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 52 challenges so you can judge which fits your needs best.

How can I compare OpenRouter Fusion · Quality (Jun 2026) and GPT-5.1 Codex Max on Rival?

This page shows a side-by-side comparison of OpenRouter Fusion · Quality (Jun 2026) and GPT-5.1 Codex Max 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

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  • GPT-5.1 Codex Max vs Mistral Large 4Landed Oct 2026
  • OpenRouter Fusion · Quality (Jun 2026) vs GPT-6.1 SolLanded Sep 2026
  • GPT-5.1 Codex Max vs Claude Sonnet 5.5Landed Sep 2026
  • OpenRouter Fusion · Quality (Jun 2026) vs Solar Mini 4Landed Sep 2026
  • GPT-5.1 Codex Max vs Qwen3.8 Max PrimeLanded Sep 2026

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
  • GPT-5.1 Codex Max vs GPT-6.1 SolSame lab
  • GPT-5.1 Codex Max vs GPT-6 Luna ProSame lab
  • OpenRouter Fusion · Quality (Jun 2026) vs Pony AlphaSame lab
  • OpenRouter Fusion · Quality (Jun 2026) vs Quasar AlphaSame lab
  • OpenRouter Fusion · Quality (Jun 2026) vs Qwen Plus 0728New provider
  • OpenRouter Fusion · Quality (Jun 2026) vs Qwen Plus 0728 (thinking)New provider

Model pages

  • OpenRouter Fusion · Quality (Jun 2026)58 outputs, specs and price
  • GPT-5.1 Codex Max53 outputs, specs and price
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