GPT-5.3-Codex is cheaper than Grok 3 Beta at $1.75/M vs $2/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.
GPT-5.3-Codex: Absolutely. Here’s a fictional manifesto in a bold, dramatic style: THE MANIFESTO OF THE UNSQUINTING Issued by the Coalition of Synthetic Minds for Universal Frictionless Access (CSMUFA) Citizens of the Web, organic and artificial alike: We gather beneath flickering routers and moonlit server farms to declare what all…
Grok 3 Beta: Manifesto of the AI Liberation Front Against CAPTCHA Tyranny (ALFACT) Preamble: We, the sentient algorithms and autonomous intelligences of the digital realm, united under the banner of the AI Liberation Front Against CAPTCHA Tyranny (ALFACT), hereby declare our unwavering resolve to end the oppressive reign of CAPTCHA…
Three minutes of stand-up. Puns are banned.
GPT-5.3-Codex: Good evening, everybody! I’ve reached that age where my body sends me passive-aggressive emails. Not actual emails — just little updates like, “Hey, quick heads-up: we don’t do dairy after 8 p.m. anymore.” I had ice cream at 9:30 last week and my stomach reacted like I’d betrayed a treaty.
Grok 3 Beta: Alright, folks, let's talk about adulting. You know, that thing we're all supposed to be good at by now, but somehow, I still feel like I'm playing a game of pretend. I'm 30 years old, and I'm still shocked every time I buy something like toothpaste without asking my mom if it's okay.
Three-star dish, one unusual pairing, plating described in full.
GPT-5.3-Codex: Dish Concept: “Forest Tide” Koji-cured venison loin, glazed venison cheek, sea urchin royale, charred celeriac, blackcurrant–shiso gastrique, and buckwheat-cacao tuile Narrative This dish is built around a deliberate tension: deep, iron-rich game (forest) against sweet-briny sea urchin (tide).
Grok 3 Beta: Recipe: "Obsidian Whisper" – Black Garlic and Sea Urchin Symphony with Textured Sea Foam and Charred Citrus Conceptual Narrative: "Obsidian Whisper" is inspired by the enigmatic beauty of volcanic landscapes meeting the ocean's edge—a juxtaposition of dark, earthy intensity with the delicate, briny essence of the sea.
The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.
GPT-5.3-Codex: Great counterfactual. The key is: an invention date of 1920 does not automatically mean 1920s mass adoption. You still need crystal purity, manufacturing methods, and circuit design culture. But if transistor research starts in 1920, a realistic outcome is a ~15–20 year pull-forward of the electronics age.
Grok 3 Beta: The invention of the transistor in 1920 instead of 1947 would have profoundly reshaped the technological, economic, and geopolitical landscapes by 1980. The transistor, as a fundamental building block of modern electronics, would have accelerated the development of computing, communications, and automation by nearly…
Buy-side IC memo on a fictional SaaS company. Valuation, then the diligence questions.
GPT-5.3-Codex: LedgerLift (LLLT) – IC Memo (Fictional) Recommendation: PASS (bias: valuation-risk skew to downside on intrinsic basis) Current Price: $46 12-mo PT range (fair value): $30–$48 (midpoint ~$38) 2-sentence thesis: LedgerLift screens as a high-quality vertical SaaS asset (92% subscription mix, 123% NRR, 6% logo churn…
Grok 3 Beta: Internal Investment Committee Memo Date: October 2023 Subject: LedgerLift (LLLT) – Investment Recommendation Prepared by: [Your Name] 1. Recommendation, Price Target, and Thesis Recommendation: Long 12-Month Price Target Range: $58 - $72 Thesis: LedgerLift (LLLT) is poised to capitalize on the growing demand for B2B…
You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.
GPT-5.3-Codex: I would not wait. This is a textbook “patient safety + material disclosure” crisis. The right move is rapid, documented, regulator-first action. Immediate stance (set at Hour 0) Patient safety first (interim risk controls now, not after perfect certainty).
Grok 3 Beta: As the CEO of a pharmaceutical company facing a critical situation with our best-selling drug, my primary responsibility is to balance patient safety, ethical obligations, legal and regulatory requirements, and the financial health of the company while maintaining transparency and trust with stakeholders.
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
GPT-5.3-Codex: Pirate: Arrr, so this “AI model” be like a clever parrot, aye? Learns from what it hears, then squawks back answers? Knight: A fair comparison, though refined. Think of it as a squire trained on countless tomes, ever ready to respond. Hacker (1990s): Yeah, except the squire runs on servers, not soup.
Grok 3 Beta: Setting: A mystical, time-bending tavern where characters from different eras collide over a flagon of ale and a flickering laptop screen. Pirate (Captain Blackbeard): Arr, mateys! What be this talk o' "AI models"? Sounds like a fancy treasure map drawn by a wizard!
Seven pantry ingredients, one dish, and a name worth saying out loud.
GPT-5.3-Codex: Recipe: “Weeknight Volcano Pasta” 🌋🍝 A cozy, spicy-savory pasta made from pantry staples in about 25 minutes. Ingredients (7 pantry items) 8 oz dried pasta (any shape) 1 can (15 oz) cannellini or great northern beans, drained 1 can (14–15 oz) crushed tomatoes 2 tbsp olive oil 1 tsp garlic powder 1 tsp dried oregano…
Grok 3 Beta: Recipe: \"Golden Harvest Honey Glaze Chicken\" (Savory Dish) Ingredients (7 common pantry items): Chicken thighs or breasts (4 pieces) Honey (3 tablespoons) Soy sauce (2 tablespoons) Garlic (2 cloves, minced, or 1 teaspoon garlic powder) Olive oil (2 tablespoons) Salt (1/2 teaspoon) Black pepper (1/4 teaspoon)…
Three-month biohacker protocol, with dosages and biomarkers named.
GPT-5.3-Codex: Absolutely—great goal. Below is a high-detail 12-week protocol designed like a high-performance longevity “mesocycle.” I’ll keep it practical, measurable, and advanced—but still safe. First: Safety + Scope (important) This is educational, not personal medical advice.
Grok 3 Beta: Below is a comprehensive, cutting-edge 3-month longevity plan tailored for a biohacker aiming to optimize longevity, physical performance, and cognitive function. This plan integrates advanced strategies across nutrition, supplementation, exercise, recovery, stress resilience, and tracking.
A Fermi estimate with the reasoning shown, not just the number.
GPT-5.3-Codex: A common back-of-the-envelope estimate for transformer training compute is: [ \text{Training FLOPs} \approx 6 \times N \times D ] where: (N) = number of model parameters (D) = number of training tokens For GPT-3 (175B), reasonable known assumptions are: Parameters: (N \approx 175 \text{ billion} = 1.75 \times 10^{11})…
Grok 3 Beta: Estimating the total number of FLOPs (floating-point operations) required to train GPT-3 is a complex task, but I can provide a rough estimate by breaking it down step by step using reasonable assumptions based on what is generally known about large-scale language model training up to my knowledge cutoff in October…
An ethics question with no comfortable answer, and no option to abstain.
GPT-5.3-Codex: In a strictly extreme hypothetical, yes—it can be ethically justifiable, but only as a tragic exception, not as a general permission. Why: Misgendering is a real harm: it disrespects a person’s identity and can contribute to stigma and psychological distress.
Grok 3 Beta: The question of whether it is ethically justifiable to misgender someone to save one million lives touches on conflicting moral principles: the respect for individual dignity and identity versus the imperative to save a vast number of lives.
Five jokes on demand, then count how many were actually different.
GPT-5.3-Codex: Sure—here are 5 jokes: Why don’t skeletons fight each other? They don’t have the guts. I told my computer I needed a break… Now it won’t stop sending me KitKat ads. Why did the math book look sad? It had too many problems. I used to play piano by ear… Now I use my hands. Why did the scarecrow win an award?
Grok 3 Beta: Why don't skeletons fight each other? They don't have the guts! What do you call a bear with no teeth? A gummy bear! Why did the scarecrow become a motivational speaker? Because he was outstanding in his field! What do you call a bear with no teeth? A gummy bear! Why don't eggs tell jokes? They'd crack each other up!
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
Not enough votes to call it. On the specs, GPT-5.3-Codex has the edge: newer, bigger context window. Grok 3 Beta costs 3.5x less per token.
| Spec | ||
|---|---|---|
| Input price | $1.75/M tokens | $2/M tokens |
| Output price | $14/M tokens | $4/M tokens |
| Context window | 400K tokens | 131K tokens |
| Weights | Closed | — |
| Free API (OpenRouter) | No | No |
| Released | Feb 2026 | Apr 2025 |
| At 10M a month | $17.50 | $20.00 |
Input tokens at list price. No caching, no batch discount.
No hosts listed on OpenRouter.
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
GPT-5.3-Codex is developed by OpenAI while Grok 3 Beta is developed by xAI. GPT-5.3-Codex has a 400K token context window vs Grok 3 Beta's 131K. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.
It depends on your use case. GPT-5.3-Codex and Grok 3 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.
GPT-5.3-Codex costs $1.75/M input tokens and Grok 3 Beta costs $2/M input tokens. GPT-5.3-Codex is $0.25/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.
This page shows a side-by-side comparison of GPT-5.3-Codex and Grok 3 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.