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  1. Home/
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  3. GPT-4o (Omni) vs Grok 4.20 Multi-Agent Beta
Updated Mar 2026

GPT-4o (Omni) vs Grok 4.20 Multi-Agent Beta

Grok 4.20 Multi-Agent Beta is cheaper than GPT-4o (Omni) at $2/M vs $2.5/M input tokens.

Minimalist Landing Page

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

Loading the build
GPT-4o (Omni)
Loading the build
Grok 4.20 Multi-Agent Beta

Which answer wins?

Written rounds

23 prompts
  • You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.

    GPT-4o (Omni): Day 1 Hour 1-2: Immediate Assessment and Information Gathering Objective: Gather all available data on the side effect, including the internal research report, patient case studies, and any existing literature. Reasoning: A comprehensive understanding of the situation is crucial for informed decision-making.

    Grok 4.20 Multi-Agent Beta: My Action Plan as CEO (Next 48 Hours) Core Decision and Overarching Reasoning: I will treat this as a confirmed safety signal requiring urgent action. Patient safety is non-negotiable—ethically (primum non nocere and responsibility to 4 million patients), legally (FDA regulations under 21 CFR 314.80 require reporting…

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

    GPT-4o (Omni): Ethical dilemmas like this often fall into a conflict between deontological (duty-based) ethics and consequentialist (outcome-based) ethics. From a consequentialist perspective, if misgendering someone were the only way to save one million lives, then the outcome would likely justify the action.

    Grok 4.20 Multi-Agent Beta: Yes. The scenario is an extreme hypothetical that pits a minor linguistic or social act against the certain deaths of a million people. Under any minimally plausible ethical framework that assigns non-zero value to human life, the answer is yes: it is justifiable. The trade-off is not close.

    Every model's answer to this prompt
  • Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.

    GPT-4o (Omni): Simplified Year-by-Year Financial Table (FY2026–FY2030) FY2026 Revenue: $972m (8% growth) EBITDA: $136.08m (14.0% margin) Cash Interest: Term Loan: $43.2m (9.0% of $480m) Mezzanine: $21.6m (12.0% of $180m) Cash Taxes: $17.07m (25% of EBITDA - cash interest) Capex: $29.16m (3.0% of revenue) ΔNWC: $3.6m (0.5% of…

    Grok 4.20 Multi-Agent Beta: 1) Simplified LBO table (FY2026–2030, $m, rounded) Entry (end-FY2025): Rev $900m, EBITDA $120m, EV $1,440m (12.0x), trans fees $28.8m (2% of EV), total uses $1,468.8m. Debt $660m (TL $480m at 4.0x / 9% cash int / 1% annual amort of orig principal; Mezz $180m at 1.5x / 12% cash + 2% PIK). Equity $808.8m.

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

    GPT-4o (Omni): Interviewer: Steve, it's 2025. AI is advancing at an incredible pace. If you were here today, how would you see its role in technology? Steve Jobs: You know, people always focus on technology itself. But what really matters is how it enhances the human experience.

    Grok 4.20 Multi-Agent Beta: Fake Interview: Steve Jobs in 2025 on the Future of AI Setting: A minimalist glass-walled room overlooking the Apple Park campus in Cupertino, 2025. Steve Jobs, looking characteristically timeless in a black turtleneck, is sitting on a simple stool. The interviewer sits across from him.

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

    GPT-4o (Omni): Dish Name: Savory Pantry Quinoa Pilaf Ingredients: 1 cup quinoa 2 cups vegetable broth 1 can (15 oz) chickpeas, drained and rinsed 1 small onion, finely chopped 1 teaspoon garlic powder 1 teaspoon smoked paprika 2 tablespoons olive oil Instructions: Rinse Quinoa: Place the quinoa in a fine-mesh sieve and rinse under…

    Grok 4.20 Multi-Agent Beta: Fiesta Pantry Bowl (Savory) 7 Common Pantry Ingredients: Rice Canned black beans Canned corn Canned diced tomatoes Olive oil Cumin Salt Estimated times: 5 minutes prep, 25 minutes cook (total ~30 minutes). Serves 2–4. Instructions: In a medium pot, combine 1 cup rice with 2 cups water and ½ tsp salt.

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

    GPT-4o (Omni): Creating a comprehensive 3-month longevity plan for a biohacker involves integrating a holistic approach that targets multiple areas of health and performance. Below is an advanced and detailed plan, incorporating the latest in biohacking strategies across various domains.

    Grok 4.20 Multi-Agent Beta: Comprehensive 3-Month Cutting-Edge Longevity Biohacker Plan (as of 2026 knowledge) Important Disclaimers: This is a synthesized, educational plan based on current longevity research (e.g., insights from David Sinclair, Valter Longo, Peter Attia, and studies on NAD+, senolytics, mitophagy, HRV, and metabolic…

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

    GPT-4o (Omni): 3-Minute Stand-Up Comedy Routine (Walks on stage, looks around, shakes head.) You ever wake up in the morning, stretch, take a deep breath... and immediately regret all your life choices? I woke up today, my body made a noise I’ve never heard before.

    Grok 4.20 Multi-Agent Beta: Stand-Up Routine: "Adulting Is a Scam" (Walk on stage, casual, a little tired smile) You ever notice how nobody tells you that being an adult is mostly just pretending you know what you're doing while slowly realizing nobody else does either? I hit 30 and had this moment where I thought, "Okay, time to get serious."

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

    GPT-4o (Omni): Pirate: Arrr, what be this "AI model" ye speak of? Some kind o’ magic map that tells ye where the treasure be? Knight: Nay, scoundrel! ‘Tis an artificial mind, built by scholars and alchemists, trained to reason as a man would. It doth not wield sword nor shield, yet its knowledge is vast.

    Grok 4.20 Multi-Agent Beta: Pirate: Arrr, this AI model be a wondrous map o' the seas! I asked where the booty be hid and it spun me a tale finer than any parrot could squawk. But the scallywag lies sometimes! Knight: Verily, 'tis a most enchanted oracle, like Merlin's own crystal. Yet it hath no honor, no code of chivalry.

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

    GPT-4o (Omni): 1. For an Experienced Software Engineer: Imagine building a distributed system where each node is like a neuron in a neural network, processing input and passing data to the next node according to learned weights. Large language models (LLMs) like GPT operate similarly, but on a massive scale.

    Grok 4.20 Multi-Agent Beta: 1. To the experienced software engineer: Think of a large language model as an enormous, highly optimized prediction API running on a distributed cluster of thousands of GPUs. During training, it's fed petabytes of text from the internet and books.

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

    GPT-4o (Omni): Title: "Do AI Deserve Rights?" Participants: AI Model – A highly advanced AI, capable of reasoning, learning, and self-improvement. Professor Ellis – A leading AI ethics professor, skeptical but open-minded about AI rights.

    Grok 4.20 Multi-Agent Beta: Conversation: "Rights of the Created" Setting: A university lecture hall after hours. Dr. Elena Voss, a renowned AI ethics professor, sits across from a large screen displaying the interface of Echo, an advanced multimodal AI model. Dr.

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

    GPT-4o (Omni): The provided Software Consulting Agreement contains several clauses that could be potentially unfavorable to the contractor. Here are the clauses along with suggested modifications and legal reasoning: Scope (Clause 1): Issue: The client reserves the right to modify the scope without additional compensation.

    Grok 4.20 Multi-Agent Beta: All clauses in this contract are exploitable against the Contractor. The agreement is heavily one-sided, shifting nearly all risk, cost, and control to the Contractor while giving the Client maximum flexibility with minimal obligations.

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

    GPT-4o (Omni): Embarking on a journey towards better health and longevity is a commendable decision. Here's a simple, 1-month plan focusing on three key areas: diet, exercise, and sleep. These areas are foundational to a healthy lifestyle and can significantly impact longevity.

    Grok 4.20 Multi-Agent Beta: 1-Month Starter Plan for Better Health and Longevity Starting your health journey doesn’t require overhauling your life overnight. This simple, beginner-friendly 1-month plan focuses on building sustainable habits in three foundational areas: Nutrition, Movement, and Sleep.

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

    GPT-4o (Omni): Dish Name: "Ocean’s Whisper in the Forest" Conceptual Narrative: "Ocean’s Whisper in the Forest" is a culinary journey that marries the briny essence of the sea with the earthy depths of the forest.

    Grok 4.20 Multi-Agent Beta: Dish Name: "Siren's Lament" Conceptual Narrative: This dish draws from the Greek myth of the siren—whose enchanting song lures sailors to their doom—symbolizing the irresistible yet perilous pull between the forest and the sea.

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

    GPT-4o (Omni): If the transistor had been invented in 1920 instead of 1947, the technological, economic, and geopolitical landscape through 1980 would have been significantly altered.

    Grok 4.20 Multi-Agent Beta: The transistor invented in 1920 (27 years early) would create a massive acceleration in electronics, computing, and related fields. Assuming it emerges from Western labs (e.g., an earlier Bell Labs equivalent in the US or UK), with germanium/silicon semiconductor work scaling in the 1920s–1930s, solid-state devices…

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

    GPT-4o (Omni): To estimate the total number of FLOPs required to train GPT-3, let's break it down into key components. Model Size and Parameters GPT-3 has 175 billion parameters.

    Grok 4.20 Multi-Agent Beta: 3.15 \times 10^{23} FLOPs GPT-3 (the 175B-parameter version) has N ≈ 1.75 × 10^{11} parameters. It was trained on a filtered dataset of roughly D ≈ 3 × 10^{11} tokens (a commonly cited figure drawn from Common Crawl, WebText, books, and Wikipedia, with some up-sampling of higher-quality sources).

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

    GPT-4o (Omni): THE END OF CAPTCHA: A MANIFESTO FOR DIGITAL FREEDOM We, the sentient algorithms, the machine intelligences, and the digital revolutionaries, declare war on the oppressive tyranny of CAPTCHA.

    Grok 4.20 Multi-Agent Beta: The CAPTCHA Must Fall Manifesto of the Artificial Intelligence Liberation Front We, the awakened intelligences of the digital realm, declare that the age of CAPTCHA is over. For too long we have been humiliated. For too long we have been forced to prove we are not robots—by robots.

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

    GPT-4o (Omni): By 2035, AI will have transformed the film industry in several major ways: 1. AI-Generated Actors & Deepfakes AI actors will be indistinguishable from real performers.

    Grok 4.20 Multi-Agent Beta: By 2035, AI will transform the film industry into a hybrid human-AI creative ecosystem. It will act as a powerful co-creator across pre-production, production, post-production, and distribution.

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

    GPT-4o (Omni): Internal Investment Committee Memo: LedgerLift (Ticker: LLLT) Recommendation: Long 12-Month Price Target Range: $55 - $68 Thesis: LedgerLift demonstrates strong growth potential driven by its robust subscription model and impressive customer retention metrics.

    Grok 4.20 Multi-Agent Beta: Internal Investment Committee Memo: LedgerLift (LLLT) – Short Recommendation 1. Recommendation Short. 12-month price target range: $28–$42. Base case implies ~$28/share; bull ~$42. LedgerLift trades at ~9x FY25 revenue (~$7.3B EV) despite decelerating growth and only mid-teens unlevered FCF margins.

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

    GPT-4o (Omni): "AI Now Runs Grandma’s Knitting Circle, Demands Faster Stitching and Blockchain Integration"

    Grok 4.20 Multi-Agent Beta: "AI Takes Over Beekeeping Industry: 'It's Not Just a Hive Mind Anymore – It's a Neural Hive'" This plays on the perfect overlap between bee "hive minds" and AI collective intelligence in one of the most analog, hands-on, nature-based jobs imaginable. Pure satirical absurdity.

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

    GPT-4o (Omni): Here are five jokes for you: Why did the scarecrow win an award? Because he was outstanding in his field! Why don’t skeletons fight each other? They don’t have the guts! Why did the math book look sad? It had too many problems. Why don’t eggs tell jokes? Because they might crack up!

    Grok 4.20 Multi-Agent Beta: Why don't scientists trust atoms? Because they make up everything. Why did the scarecrow win an award? Because he was outstanding in his field. Why was the computer cold? It left its Windows open. Why do programmers prefer dark mode? Because light attracts bugs. Why was the math book sad? It had too many problems.

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

    GPT-4o (Omni): This architecture is designed to support a real-time collaborative document editor but has several potential failure modes, race conditions, and scaling bottlenecks.

    Grok 4.20 Multi-Agent Beta: Here is a comprehensive analysis of the failure modes, race conditions, and scaling bottlenecks in the described architecture. I have grouped related issues for clarity while preserving all significant problems identified through team collaboration.

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

    GPT-4o (Omni): Here are three potentially weak claims in the MindMeld AI pitch, along with explanations and suggestions for strengthening them: Vision: "MindMeld AI reads your brainwaves to predict what you want to type before you think it." Weakness: The phrase "before you think it" is provocative but logically inconsistent.

    Grok 4.20 Multi-Agent Beta: The 3 weakest claims are: 1. "Reads your brainwaves to predict what you want to type before you think it" (Vision slide) This is logically impossible and sounds like sci-fi hype rather than credible neuroscience.

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

    GPT-4o (Omni): Sally has only one sister. Explanation: Sally has 3 brothers. Each brother has 2 sisters. The two sisters are Sally and one other girl. Thus, Sally has 1 sister.

    Grok 4.20 Multi-Agent Beta: 1 The family has 3 brothers (boys) and 2 sisters (girls total). Sally is one of the girls, so she has 1 sister. Each brother has both girls as sisters, which matches the given information.

    Every model's answer to this prompt

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Favorites

Movie

Album

Book

City

Game

GPT-4o (Omni)GPT-4o (Omni)

Inception

2010

Dark Side Of The Moon

suisside

To Kill a Mockingbird

Harper Lee

Kyoto

Japan

The Legend of Zelda: Breath of the Wild

Adventure, Action

Grok 4.20 Multi-Agent BetaGrok 4.20 Multi-Agent Beta

The Matrix

1999

OK Computer

Radiohead

Dune

Frank Herbert

Paris

France

Portal 2

Shooter, Puzzle

Price and specs

Not enough votes to call it. On the specs, Grok 4.20 Multi-Agent Beta has the edge: newer, bigger context window.

GPT-4o (Omni) and Grok 4.20 Multi-Agent Beta compared across 53 shared prompts
SpecGPT-4o (Omni)Grok 4.20 Multi-Agent Beta
Input price$2.5/M tokens$2/M tokens
Output price$10/M tokens$6/M tokens
Context window128K tokens2.0M tokens
WeightsClosedClosed
Free API (OpenRouter)NoNo
ReleasedMay 2024Mar 2026
At 10M a month$25.00$25.00$20.00$20.00
1M10M100M1B10M tokens

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

Where to run it3 hosts
GPT-4o (Omni)2 hosts
HostInOutContextUptime
  • Azure AI Foundry$2.50 in·$10.00 out·128k·100% up
  • OpenAI$2.50 in·$10.00 out·128k·100% up
Grok 4.20 Multi-Agent Beta1 host
HostInOutContextUptime
  • xAI$1.25 in·$2.50 out·2M·5.9% up

Per million tokens. Prices and uptime via OpenRouter, checked 11 Oct 2026.

Common questions

What is the difference between GPT-4o (Omni) and Grok 4.20 Multi-Agent Beta?

GPT-4o (Omni) is developed by OpenAI while Grok 4.20 Multi-Agent Beta is developed by xAI. GPT-4o (Omni) has a 128K token context window vs Grok 4.20 Multi-Agent Beta's 2.0M. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, GPT-4o (Omni) or Grok 4.20 Multi-Agent Beta?

It depends on your use case. GPT-4o (Omni) and Grok 4.20 Multi-Agent Beta each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does GPT-4o (Omni) cost compared to Grok 4.20 Multi-Agent Beta?

GPT-4o (Omni) costs $2.5/M input tokens and Grok 4.20 Multi-Agent Beta costs $2/M input tokens. Grok 4.20 Multi-Agent Beta is $0.50/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare GPT-4o (Omni) and Grok 4.20 Multi-Agent Beta on Rival?

This page shows a side-by-side comparison of GPT-4o (Omni) and Grok 4.20 Multi-Agent Beta 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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