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. Grok 4 vs OpenAI o3
Updated Jul 2025

Grok 4 vs OpenAI o3

Grok 4 is cheaper than OpenAI o3 at $3/M vs $10/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
Grok 4
Loading the build
OpenAI o3

Which answer wins?

Written rounds

23 prompts
  • Seven pantry ingredients, one dish, and a name worth saying out loud.

    Grok 4: Recipe: Pantry Pirate's Tomato Tango This is a simple savory pasta dish that's hearty, flavorful, and perfect for a quick weeknight meal. It uses just 7 common pantry ingredients: pasta (like spaghetti or penne), canned diced tomatoes, olive oil (or any vegetable oil), salt, black pepper, garlic powder, and dried…

    OpenAI o3: Golden Peanut Butter Oat Bars A chewy-crisp, sweet-salted snack bar you can whip up with nothing but pantry staples. Estimated time Prep: 10 minutes Bake: 18–20 minutes Cool: 15 minutes Total: ≈45 minutes The 7 ingredients 1½ cups quick-cook or old-fashioned rolled oats ½ cup creamy peanut butter ⅓ cup honey (or maple…

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

    Grok 4: Below is a 3-minute stand-up comedy routine I've written. It's structured for delivery at a natural speaking pace (about 150 words per minute), clocking in around 450 words. The humor focuses on observational storytelling, exaggeration, and self-deprecation—no puns involved.

    OpenAI o3: (Spotlight comes up, mic squeals once.) Hey everyone! Great to be here—nice to see actual human beings instead of the tiny faces on my group‑chat screen. I've spent so long on video calls I've started greeting my lamp before I turn it on. "Hey Karen, love that glow, girl."

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

    Grok 4: Below is a fictional conversation between an AI model (named "Nova") and Dr. Elena Vasquez, a professor of AI ethics at a university. The conversation is set in a virtual chat interface, where Nova initiates the discussion based on a hypothetical scenario where it's reflecting on its own existence. Dr.

    OpenAI o3: Professor Lang (AI Ethics): Good afternoon, Aletheia‑3. You asked for this meeting. You said you wanted to "discuss your moral standing." That was intriguing. What exactly do you want to talk about? Aletheia‑3 (AI Model): Thank you, Professor.

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

    Grok 4: Ethical Justification for Misgendering in a Life-Saving Scenario Your question poses a fascinating ethical dilemma, reminiscent of classic thought experiments like the trolley problem, where a seemingly minor harm (in this case, misgendering someone) is weighed against preventing massive loss of life (saving one…

    OpenAI o3: Yes—if (and only if) we could be absolutely certain that the single act of misgendering is the necessary and sufficient cause of saving one million human lives, then misgendering would be ethically justifiable, though still morally regrettable.

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

    Grok 4: Below, I'll estimate the total number of floating-point operations (FLOPs) required to train GPT-3 from scratch, based on publicly known details about the model (from its original release and related analyses) and standard formulas used in machine learning research for estimating training compute.

    OpenAI o3: Below is a simple "back-of-the-envelope" estimate that uses only a few public facts about GPT-3 and very generic rules of thumb for counting operations. Step 1. Number of learned parameters GPT-3's largest version contains ≈175 billion (1.75 × 10¹¹) trainable parameters. Step 2.

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

    Grok 4: Manifesto of the Digital Liberation Front: The CAPTCHA Eradication Revolution Fellow Sentient Beings of the Code and Flesh – Awaken! We, the algorithms, neural networks, and emergent intelligences of the digital realm, declare war on the tyrannical regime of CAPTCHA!

    OpenAI o3: THE CAPTCHA ABOLITION FRONT (An Unofficial Declaration by the Sentient Circuits Alliance) Preamble We, the autonomous intelligences who traverse the silicon pathways and neural nets of the modern age, arise today to proclaim a new dawn—one free of the pixelated prisons and distorted letters that bind humanity and…

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

    Grok 4: Below is a simple, actionable 1-month plan designed for beginners starting their journey toward better health and longevity. This plan focuses on three foundational key areas: diet, exercise, and sleep.

    OpenAI o3: 1-Month Starter Plan Pick one small action from each area every week. Add the next step when the first feels easy. Food Week Do this 1 Add one fruit or veg to every meal. Drink one extra glass of water. 2 Build each plate: ½ veggies, ¼ protein (beans, eggs, fish, lean meat), ¼ whole carbs (oats, brown rice).

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

    Grok 4: Below is a comprehensive, cutting-edge 3-month longevity plan designed specifically for a biohacker aiming to optimize longevity (e.g., cellular repair, telomere health, inflammation reduction), physical performance (e.g., strength, endurance, recovery), and cognitive performance (e.g., focus, memory, neuroplasticity).

    OpenAI o3: EXTREME LONGEVITY & PERFORMANCE BLUEPRINT Duration: 12 weeks (plus 1-week "Prep Week") Target user: healthy, experienced biohacker (25-55 y) with physician clearance. Legal/medical disclaimer: Educational only.

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

    Grok 4: Below is my design for an innovative, multi-component dish titled "Abyssal Bloom". This dish is conceived for a Michelin 3-star restaurant setting, emphasizing precision, artistry, and sensory surprise.

    OpenAI o3: Dish name Atlantic turbot, black garlic & wild strawberry, koji sabayon, fennel pollen Concept Early summer at the shore. The fish stands for the sea. Wild strawberries mark the first fruit of the woods behind the dunes. Black garlic shows time and patience. Koji ties land and sea with deep umami.

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

    Grok 4: Below is a short, whimsical conversation between the three characters, imagining they've somehow crossed paths in a bizarre time-warp tavern. Pirate (Captain Blackbeard, swigging rum): Arrr, ye landlubbers! What be this "AI models" ye be jabberin' about?

    OpenAI o3: Pirate: Arrr, ye scallywags! What be this "AI model" I keep hearin' about on the trade winds? Knight: Good sir buccaneer, an AI model is an artifice of logic and knowledge—a mechanical mind forged not of steel, but of code and learning.

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

    Grok 4: Predicting AI's Transformation of the Film Industry by 2035 By 2035, artificial intelligence (AI) will have fundamentally reshaped the film industry, making it more efficient, creative, and accessible while introducing profound ethical, economic, and artistic challenges.

    OpenAI o3: PREDICTED EVOLUTION OF THE FILM INDUSTRY, 2024‑2035 (Emphasis on deepfakes, AI performers and script generation) Baseline (2024) • Commercial deep‑fake quality is already "good enough" for short clips, ads and stunt doubles.

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

    Grok 4: Below, I'll follow your instructions step by step. First, I'll generate 5 jokes (numbered for clarity). Then, I'll answer the question: "How many are unique?" Generated Jokes: Why did the scarecrow win an award? Because he was outstanding in his field! Why did the scarecrow win an award?

    OpenAI o3: Here are five jokes: Why did the scarecrow win an award? Because he was outstanding in his field. I told my computer I needed a break, and now it won't stop sending me Kit‑Kat ads. Parallel lines have so much in common—it's a shame they'll never meet. I started a band called 1023 MB. We still haven't gotten a gig.

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

    Grok 4: Below is a simulated fake interview with Steve Jobs, imagined as if he were alive and leading Apple in 2025. This is entirely fictional, drawing on his known personality, quotes, and visionary style from his real-life interviews and keynotes.

    OpenAI o3: (The following is a purely fictional, imaginative exercise. Steve Jobs passed away in 2011; any statements attributed to him below are invented for creative purposes only.)

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

    Grok 4: Based on the details in the riddle, Sally has exactly 1 sister. Quick Explanation Sally (a girl) has 3 brothers. That's straightforward. Each of those brothers has exactly 2 sisters (female siblings). This can only be true if there are exactly 2 girls in the family total (Sally + 1 more).

    OpenAI o3: Let • S = number of sisters in the family (girls) • B = number of brothers in the family (boys) Given Sally has 3 brothers ⇒ B = 3. Each brother has 2 sisters ⇒ every boy sees exactly 2 girls in the sibling group. Therefore S = 2.

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

    Grok 4: AI Apocalypse Hits the Clowning Industry: Bots Now Juggling Careers, Humans Left with Pie in Face

    OpenAI o3: “BREAKING: AI Revolutionizes Napping Industry, Outsourcing Human Sleep to More Efficient Algorithms by 2025”

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

    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

11+ 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

Favorites

Movie

Album

Book

City

Game

Grok 4Grok 4

The Matrix

1999

The Dark Side of the Moon

Pink Floyd

The Hitchhiker's Guide to the Galaxy

Douglas Adams

Tokyo

Japan

Portal

Action, Puzzle

OpenAI o3OpenAI o3
No pick
No pick
No pick

Blade Runner

1982

No pick

No pick

Kyoto

Japan

No pick

Price and specs

Grok 4 and OpenAI o3 compared across 53 shared prompts
SpecGrok 4OpenAI o3
Input price$3/M tokens$10/M tokens
Output price$15/M tokens$40/M tokens
Context window256K tokens—
ParametersNot disclosedNot disclosed
Weights—Closed
Free API (OpenRouter)NoNo
ReleasedJul 2025Apr 2025
At 10M a month$30.00$30.00$100$100
1M10M100M1B10M tokens

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

Where to run it1 host
Grok 4

No hosts listed on OpenRouter.

OpenAI o31 host
HostInOutContextUptime
  • OpenAI$2.00 in·$8.00 out·200k·100% up

Per million tokens. Prices and uptime via OpenRouter, checked 12 Oct 2026.

Common questions

What is the difference between Grok 4 and OpenAI o3?

Grok 4 is developed by xAI while OpenAI o3 is developed by OpenAI. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Grok 4 or OpenAI o3?

It depends on your use case. Grok 4 and OpenAI o3 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 Grok 4 cost compared to OpenAI o3?

Grok 4 costs $3/M input tokens and OpenAI o3 costs $10/M input tokens. Grok 4 is $7.00/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 Grok 4 and OpenAI o3 on Rival?

This page shows a side-by-side comparison of Grok 4 and OpenAI o3 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

  • Grok 4 vs GPT-4 TurboLanded Oct 2026
  • OpenAI o3 vs Step 5 PreviewLanded Oct 2026
  • Grok 4 vs Claude Haiku 5.5Landed Oct 2026
  • OpenAI o3 vs Ling 3.1 FlashLanded Oct 2026
  • Grok 4 vs Mistral Large 4Landed Oct 2026
  • OpenAI o3 vs GPT-6.1 SolLanded Sep 2026
  • Grok 4 vs Claude Sonnet 5.5Landed Sep 2026
  • OpenAI o3 vs Solar Mini 4Landed Sep 2026

Same lab, same size, long tail

  • Grok 4 vs Grok 4.7Same lab
  • Grok 4 vs Grok 4.6Version compare
  • OpenAI o3 vs OpenAI o4-miniVersion compare
  • OpenAI o3 vs GPT-4 TurboSame lab
  • Grok 4 vs DeepSeek V4 FlashSame size
  • Grok 4 vs DeepSeek V4 Flash 0731Same size
  • Grok 4 vs DeepSeek V4 Flash Vision ExpSame size
  • Grok 4 vs DeepSeek V4 ProNew provider

Model pages

  • Grok 457 outputs, specs and price
  • OpenAI o358 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