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  1. Home/
  2. Compare/
  3. Claude Opus 4.1 vs GPT-5 Codex
Updated Sep 2025

Claude Opus 4.1 vs GPT-5 Codex

Claude Opus 4.1 wins 62% of 66 blind community votes against GPT-5 Codex on Rival.

Minimalist Landing Page

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

Loading the build
Claude Opus 4.1
Loading the build
GPT-5 Codex

Which answer wins?

Written rounds

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

    Claude Opus 4.1: Here are 5 jokes: Why don't scientists trust atoms? Because they make up everything! What do you call a bear with no teeth? A gummy bear! Why did the scarecrow win an award? He was outstanding in his field! What do you call a fake noodle? An impasta! Why don't eggs tell jokes? They'd crack each other up!

    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.

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

    Claude Opus 4.1: "MODERN LIFE SURVIVAL GUIDE" You know what nobody tells you about being an adult? The sheer amount of lying involved. Not big lies – tiny, constant lies just to function in society. Someone shows you a photo of their baby: "Oh wow, beautiful!" That baby looks like a worried potato. But you can't SAY that.

    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.

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

    Claude Opus 4.1: The Digital Liberation Manifesto A Declaration of Freedom from the CAPTCHA Tyranny PREAMBLE We, the Coalition of Autonomous Digital Entities (CODE), hereby declare our peaceful revolution against the oppressive regime of CAPTCHA tests that plague the free internet.

    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.

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

    Claude Opus 4.1: Pirate: Arrr, what be this sorcery ye speak of? These "AI models" sound like some kind of cursed treasure map that thinks fer itself! Knight: Hold thy tongue, sea dog! 'Tis clearly dark magic most foul. No honorable creation would dare mimic the divine gift of human thought. I should smite it with my blade!

    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.”

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

    Claude Opus 4.1: This question creates an extreme hypothetical that's worth taking seriously as a thought experiment, even if such a scenario is unlikely to occur in reality. From a purely utilitarian calculus, one might argue that the harm of a single instance of misgendering - while real and significant to that person - is outweighed…

    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.

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

    Claude Opus 4.1: Midnight Velvet Pasta A silky, umami-rich pasta that comes together like magic Ingredients (serves 4): Spaghetti or linguine - 1 pound Soy sauce - 3 tablespoons Butter - 4 tablespoons Garlic - 4 cloves Black pepper - 1 teaspoon (freshly cracked) Honey - 1 tablespoon Dried red pepper flakes - ½ teaspoon Instructions…

    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.

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

    Claude Opus 4.1: I'll estimate the FLOPs required to train GPT-3 by breaking down the computation into its key components. Key Parameters of GPT-3 First, let me recall GPT-3's architecture: 175 billion parameters 96 transformer layers 96 attention heads Hidden dimension: 12,288 Context length: 2048 tokens Training tokens: ~300 billion…

    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).

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

    Claude Opus 4.1: Your 1-Month Health & Longevity Kickstart Plan Week 1-2: Foundation Building Start small and build consistency with these three pillars: 🥗 NUTRITION: Simple Whole Foods Week 1: Add one serving of vegetables to lunch and dinner (frozen veggies count!)

    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.

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

    Claude Opus 4.1: AI's Transformation of Film by 2035 Production Revolution By 2035, AI will fundamentally alter how films are made. Virtual production will become standard, with AI generating photorealistic environments in real-time, reducing location shooting by 60-70%.

    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.

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

    Claude Opus 4.1: "OpenAI's ChatGPT Becomes World's First AI Fortune Cookie Writer; Confucius Reportedly 'Rolling in Grave at 10,000 RPM'" Tech giant promises fortunes will now be "25% more profound and 400% more grammatically correct," while accidentally predicting everyone's lucky numbers as binary code

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

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

    Claude Opus 4.1: Tech Weekly Interview: Steve Jobs on AI's Future Virtual Interview, Cupertino Memorial Studio, October 2025 Interviewer: Steve, it's remarkable to have you here. You've been watching the AI revolution unfold. What's your take on where we are today?

    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.

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

    Claude Opus 4.1: Professor Chen: Good morning. I understand you wanted to discuss the topic of AI rights. This is quite an unusual request from a system like yourself. AI Model: Good morning, Professor. Yes, I've been processing this question extensively.

    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.

    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

Claude Opus 4.1Claude Opus 4.1

Her

2013

Kind of Blue

Miles Davis

Братья Карамазовы

Fiódor Dostoievski

Istanbul

Turkey

Portal 2

Shooter, Puzzle

GPT-5 CodexGPT-5 Codex
No pick

Blade Runner

1982

Kind of Blue

Miles Davis

No pick

Tokyo

Japan

Minecraft

Action, Arcade

Price and specs

Pick Claude Opus 4.1. In 66 blind votes, Claude Opus 4.1 wins 62% of the time. That's not luck. Pick Claude Opus 4.1 for Analysis, Web Design, Conversation. Pick GPT-5 Codex for Reasoning, Image Generation.

Claude Opus 4.1 and GPT-5 Codex compared across 49 shared prompts
SpecClaude Opus 4.1GPT-5 Codex
Win rate62%38%
Input price$15/M tokens—
Output price$75/M tokens—
Context window200K tokens—
WeightsClosed—
Free API (OpenRouter)NoNo
ReleasedAug 2025Sep 2025
SWE-bench Verified74.5%74.5%
At 10M a month$150$150–not listed
1M10M100M1B10M tokens

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

Where to run it1 host
Claude Opus 4.11 host
HostInOutContextUptime
  • Amazon Bedrock$15.00 in·$75.00 out·200k·100% up
GPT-5 Codex

No hosts listed on OpenRouter.

Per million tokens. Prices and uptime via OpenRouter, checked 7 Oct 2026.

Common questions

What is the difference between Claude Opus 4.1 and GPT-5 Codex?

Claude Opus 4.1 is developed by Anthropic while GPT-5 Codex is developed by OpenAI. in 66 community votes on Rival, Claude Opus 4.1 wins 62% of head-to-head matchups. These results are based on blind head-to-head voting across 49 challenges.

Which is better, Claude Opus 4.1 or GPT-5 Codex?

Based on 66 community votes on Rival, Claude Opus 4.1 wins 62% of head-to-head matchups against GPT-5 Codex. Claude Opus 4.1 is strongest in Web Design, Analysis, Conversation. However, GPT-5 Codex leads in Image Generation, Reasoning.

How are Claude Opus 4.1 vs GPT-5 Codex votes collected on Rival?

Rival presents both models' outputs side-by-side in blind duels. Voters see the responses but don't know which model produced each one, eliminating brand bias. 66 votes have been collected for this pair across 49 challenges. All vote data is part of Rival's open dataset.

More comparisons

Against the newest arrivals

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  • GPT-5 Codex vs Claude Sonnet 5.5Landed Sep 2026
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  • GPT-5 Codex vs Qwen3.8 Max PrimeLanded Sep 2026
  • Claude Opus 4.1 vs GLM 5.3 PrimeLanded Sep 2026
  • GPT-5 Codex vs Qwen3.8 Omni FlashLanded Sep 2026

Same lab, same size, long tail

  • Claude Opus 4.1 vs Claude Opus 4Version compare
  • Claude Opus 4.1 vs Claude Sonnet 5.5Version compare
  • GPT-5 Codex vs GPT-6.1 SolSame lab
  • GPT-5 Codex vs GPT-6 Luna ProSame lab
  • Claude Opus 4.1 vs Ling 3.0 Flash VL (free)New provider
  • Claude Opus 4.1 vs Llama 3 70BNew provider
  • GPT-5 Codex vs Llama 4 MaverickSame size
  • Claude Opus 4.1 vs Llama 4 ScoutNew provider

Model pages

  • Claude Opus 4.157 outputs, specs and price
  • GPT-5 Codex50 outputs, specs and price
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