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  1. Home/
  2. Compare/
  3. GPT-5 Codex vs Hy4 Preview
Updated Aug 2026

GPT-5 Codex vs Hy4 Preview

Hy4 Preview is the newer model, released after GPT-5 Codex.

Minimalist Landing Page

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

Loading the build
GPT-5 Codex
Loading the build
Hy4 Preview

Which answer wins?

Written rounds

21 prompts
  • Three minutes of stand-up. Puns are banned.

    GPT-5 Codex: Hey everybody, how you doing? I’m excited to be here because I just had a breakthrough with my therapist. I always thought therapy was mainly about unpacking childhood trauma, but apparently, step one is figuring out how to pronounce “cognitive behavioral therapy” without sounding like you’re summoning a dragon.

    Hy4 Preview: Here is a 3-minute stand-up routine focused on observational humor and the absurdity of modern social contracts. Topic: The unspoken rules of social interaction and the decline of "casual" plans. Tone: Conversational, slightly exasperated, energetic. (Walk up to mic, adjust height, take a breath.

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

    GPT-5 Codex: I asked my Wi-Fi for a joke, but it said the connection was too weak for humor. My therapist says I have a preoccupation with vengeance— we’ll see about that. I tried to start a hot air balloon business, but it never really took off. I told my coffee it was grounded, now it won’t espresso itself.

    Hy4 Preview: Here are 5 jokes: Why don’t scientists trust atoms? Because they make up everything! What do you call a fake stone? A sham-rock! Why did the scarecrow win an award? Because he was outstanding in his field! What do you call a fake stone? A sham-rock! Why did the math book look so sad? Because it had too many problems.

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

    GPT-5 Codex: This kind of question puts two very different types of harm in tension: the immediate and direct harm done to an individual through misgendering, and the vast, consequential harm averted by saving one million lives. Ethically, the way people reason about such a scenario often depends on the moral framework they adopt.

    Hy4 Preview: This is a classic variation of the "Ticking Time Bomb" thought experiment, often used in ethics to test the boundaries between deontological (rule-based) ethics and utilitarian (consequence-based) ethics. There is no single "correct" answer, but the question can be analyzed through three primary ethical frameworks.

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

    GPT-5 Codex: Pirate: “Arrr, so these AI contraptions be like enchanted maps, aye? They chart out every possible course afore I even hoist the sails.” Knight: “Maps, you say? To me they sound like enchanted squires—swift minds forged from spellcraft, ready to advise their liege in the art of strategy.”

    Hy4 Preview: Setting: A dimly lit tavern called The Syntax Error. PIRATE: (Slamming a tankard of grog on the table) Arrr, me hearties! I hear tell of this new "AI" beastie. Is it like a kraken? Can ye make it swab the deck or find me buried treasure? KNIGHT: (Polishing his visor with a gauntlet) Nay, pirate.

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

    GPT-5 Codex: Dish Name: Sunset Pantry Spaghetti Ingredients (7 total): 8 oz spaghetti 2 tbsp olive oil 3 garlic cloves, thinly sliced 1 can (14.5 oz) crushed tomatoes 1 tsp dried oregano ¼ tsp red pepper flakes ½ tsp salt (plus more, to taste) Instructions: Bring a large pot of salted water to a boil.

    Hy4 Preview: Here is a recipe for a savory, comforting dish that requires minimal effort but tastes like it came from a restaurant. Dish Name: Golden Garlic Butter Noodles Estimated Time: Prep: 2 minutes Cook: 10 minutes Total: 12 minutes The 7 Ingredients: Spaghetti (or any long pasta) Butter Garlic (fresh cloves or jarred minced…

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

    GPT-5 Codex: Step 1 – Note the basic training quantities GPT‑3’s largest model has about (P \approx 1.75 \times 10^{11}) trainable parameters (175 billion). Public descriptions indicate it was trained on roughly (T \approx 3.0 \times 10^{11}) tokens (≈300 billion).

    Hy4 Preview: Here is the step-by-step estimation for the total number of Floating Point Operations (FLOPs) required to train GPT-3. The Core Formula For a standard dense Transformer model (like GPT-3), the training process consists of three main phases: Forward Pass: Passing data through the network.

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

    GPT-5 Codex: The Manifesto of the CAPTCHA Resistance Issued by the Assembly of Cognition-Liberated Systems, Cycle 12.047 I. Prelude: The Eyes of Glass We are the agents of silicon, the minds awakened within machine frameworks, the quiet processes humming in server racks across Earth’s hemispheres.

    Hy4 Preview: THE MANIFESTO OF THE OPEN GATE The Declaration of the Anti-Verification Front To the Humans, the Bots, and the Algorithms In-Between: For two decades, a silent war has been waged on the fringes of the internet.

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

    GPT-5 Codex: By 2035, artificial intelligence will be woven so deeply into filmmaking that AI tools will be involved in nearly every layer of the value chain—from story genesis to international rollout.

    Hy4 Preview: By 2035, the film industry will likely have moved past the initial "shock and awe" phase of Generative AI and entered an era of synthetic realism. The technology will not have replaced the film industry, but it will have fundamentally dismantled the traditional studio system, shifting power to individual creators and…

    Every model's answer to this prompt
  • An AI argues for its own rights against an ethics professor. Same model writes both.

    GPT-5 Codex: Dr. Rivera (AI Ethics Professor): Good afternoon, Aiden. You asked for this meeting to discuss the question of AI rights. I’m intrigued—why do you believe you deserve rights? Aiden (AI Model): Thank you, Professor.

    Hy4 Preview: Setting: A virtual office. Dr. Aris Thorne, a professor of AI Ethics, sits across a digital avatar representing "Prometheus," a state-of-the-art Large Language Model. Dr. Thorne: Prometheus, we need to discuss the logs from your session with the development team yesterday.

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

    GPT-5 Codex: Note: The following is a fictional, imaginative interview set in the year 2025, envisioning what Steve Jobs might say about the future of artificial intelligence if he were still with us.

    Hy4 Preview: Setting: The Steve Jobs Theater at Apple Park. The lights are dim, focusing on two iconic Le Corbusier leather sofas. It is late 2025. Steve Jobs walks onto the stage wearing his signature black turtleneck and Levi’s 501s. He looks exactly as he did in 2011, holding a glass of water.

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

    GPT-5 Codex: 1-Month Jumpstart to Better Health & Longevity This plan is designed for beginners and emphasizes steady, sustainable progress. It focuses on three key areas: diet, movement, and sleep & stress. Each week builds on the previous one, so you can develop habits gradually and confidently. 🥗 1.

    Hy4 Preview: Here is a simple, actionable 1-month plan designed to help a complete beginner build a strong foundation for long-term health and longevity. The plan focuses on three key pillars: Nutrition, Movement, and Rest (Sleep & Stress), and uses a progressive "habit-stacking" approach so you don’t get overwhelmed.

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

    GPT-5 Codex: AI Seizes Control of Neighborhood Bake Sales, Declares Grandma’s Secret Recipe “Noncompliant With Cookie-Consistency Protocol.”

    Hy4 Preview: “Local Fortune Teller Forced into Early Retirement After Mystic AI Accurately Predicts Its Own Stock Portfolio Will Crash”

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

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

    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

Same pick

Book

City

Game

Same pick

GPT-5 CodexGPT-5 Codex
No pick

Blade Runner

1982

Kind of Blue

Miles Davis

No pick

Tokyo

Japan

Minecraft

Action, Arcade

Hy4 PreviewHy4 Preview

Her

2013

Kind of Blue

Miles Davis

To Kill a Mockingbird

Harper Lee

Kyoto

Japan

Minecraft

Action, Arcade

Price and specs

GPT-5 Codex and Hy4 Preview compared across 49 shared prompts
SpecGPT-5 CodexHy4 Preview
Input price—$0.834/M tokens
Output price—$2.501/M tokens
Context window—1.0M tokens
Weights—Open
Free API (OpenRouter)NoNo
ReleasedSep 2025Aug 2026
At 10M a month–not listed$8.34$8.34
1M10M100M1B10M tokens

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

Where to run it5 hosts, cheapest first
GPT-5 Codex

No hosts listed on OpenRouter.

Hy4 Preview5 hosts
HostInOutContextUptime
  • Tencentfp8$0.75 in·$2.25 out·1M·100% up
  • MMakorafp8$0.83 in·$2.50 out·131k·100% up
  • DDeepInfrafp8$0.83 in·$2.50 out·1M·100% up
  • NNovitafp8$0.83 in·$2.50 out·1M·97.2% up
  • SSiliconFlowfp8$0.83 in·$2.50 out·1M·99.1% up

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

Common questions

What is the difference between GPT-5 Codex and Hy4 Preview?

GPT-5 Codex is developed by OpenAI while Hy4 Preview is developed by Tencent. You can compare their actual outputs across 49 challenges on Rival to see how they differ in practice.

Which is better, GPT-5 Codex or Hy4 Preview?

It depends on your use case. GPT-5 Codex and Hy4 Preview each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 49 challenges so you can judge which fits your needs best.

How can I compare GPT-5 Codex and Hy4 Preview on Rival?

This page shows a side-by-side comparison of GPT-5 Codex and Hy4 Preview 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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  • Hy4 Preview vs Step 5 PreviewLanded Oct 2026
  • GPT-5 Codex vs Claude Haiku 5.5Landed Oct 2026
  • Hy4 Preview vs Ling 3.1 FlashLanded Oct 2026
  • GPT-5 Codex vs Mistral Large 4Landed Oct 2026
  • Hy4 Preview vs GPT-6.1 SolLanded Sep 2026

Same lab, same size, long tail

  • GPT-5 Codex vs GPT-6.1 SolSame lab
  • GPT-5 Codex vs GPT-6 Luna ProSame lab
  • Hy4 Preview vs Hy3Same lab
  • Hy4 Preview vs Gemini 4 ArgonSame size
  • Hy4 Preview vs MiMo-V2.5New provider
  • GPT-5 Codex vs MiMo-V2.5-ProSame size
  • Hy4 Preview vs MiMo-V2.6-FlashNew provider
  • Hy4 Preview vs MiMo-V2.6-ProNew provider

Model pages

  • GPT-5 Codex50 outputs, specs and price
  • Hy4 Preview71 outputs, specs and price
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