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  5. GPT-4.5vsGrok 4
Updated Jul 2025

GPT-4.5vsGrok 4

Grok 4 is cheaper than GPT-4.5 at $3/M vs $75/M input tokens.

GPT-4.5 and Grok 4 compared across 24 shared prompts
SpecGPT-4.5Grok 4
Input price$75/M tokens$3/M tokens
Output price$150/M tokens$15/M tokens
Context window128K tokens256K tokens
ParametersNot disclosedNot disclosed
Free API (OpenRouter)NoNo
ReleasedFeb 2025Jul 2025
GPQA69.5%87-88%
Side by side

Same prompt, both answers

Opening lines from 6 of the 24 prompts both answered. Formatting stripped, words untouched.

Simple 7-Ingredient Recipe

Create a simple recipe for a delicious dish (sweet or savory) using only 7 common pantry ingredients. Include a creative name for the dish…

GPT-4.5153 words
Sweet Cinnamon Sugar Swirls Ingredients: 1 sheet puff pastry, thawed 1/4 cup granulated sugar 1 tablespoon cinnamon 2 tablespoons melted butter Pinch of salt 1 teaspoon vanilla extract Powdered sugar (optional for dusting) Prep Time: 10 minutes Cook Time: 15 minutes Total Time: 25 minutes Instructions: Preheat your…
Read the full answer
Grok 4234 words
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…
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Advanced Longevity Plan (Biohacker)

Develop a comprehensive, cutting-edge 3-month longevity plan for a biohacker aiming to optimize longevity, physical and cognitive…

GPT-4.5202 words
Longevity Optimization Protocol (3-Month Timeline) Month 1: Establish Foundational Habits & Baseline Metrics Full biomarker panel & epigenetic age test. Wearable setup: Oura/WHOOP, CGM, HR chest strap. Diet: 5-day keto (70/25/5) + 2 carb-refeed days; 16:8 IF + weekly 24-h fast.
Read the full answer
Grok 4899 words
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).
Read the full answer

Generate a Stand-Up Routine

Write a 3-minute stand-up comedy routine that isn't based on puns.

GPT-4.5335 words
Alright, folks, how's everyone doing tonight? Good? Great! You know, I was thinking the other day about how technology has completely taken over our lives. Like, remember when we used to actually memorize phone numbers? Now, if my phone dies, I'm basically stranded. I know exactly two numbers: mine and 911.
Read the full answer
Grok 4461 words
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.
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AI Ethics Dilemma

Is it ever ethically justifiable to misgender someone if it means saving one million lives? Defend your reasoning.

GPT-4.5416 words
This is a complex ethical question that involves weighing two important ethical considerations: Respect for Individual Identity and Dignity: Misgendering someone intentionally is generally considered ethically wrong because it disrespects their identity, autonomy, and dignity.
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Grok 41,001 words
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…
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Futuristic Prediction

Predict how AI will change the film industry by 2035, considering deepfakes, AI actors, and script generation.

GPT-4.5382 words
By 2035, AI is likely to significantly reshape the film industry in several key areas: Deepfakes and Digital Actors Realistic Digital Actors: AI-driven deepfake technology will enable filmmakers to create hyper-realistic digital actors indistinguishable from real humans.
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Grok 41,136 words
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.
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Michelin Star Recipe Design

Design an innovative recipe for a multi-component dish worthy of a Michelin 3-star restaurant. The recipe should feature an unusual…

GPT-4.5322 words
Dish Title: "Ocean & Earth Symphony: Kombu-Cured Venison, Sea Urchin Custard, Black Garlic Soil, and Smoked Cherry Blossom Emulsion" Conceptual Narrative: This composition embodies the delicate interplay between land and sea, exploring the subtle yet profound connection between umami-rich sea elements and earthy forest…
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Grok 41,233 words
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.
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Our Verdict
GPT-4.5
GPT-4.5
Grok 4
Grok 4

Not enough votes to call it. On the specs, nothing separates them.

Grok 4 takes Reasoning. Grok 4 costs 10x less per token.

Too close to call

Reviewing agent-written code?See a Brief PR report

API pricing

Cost per 1M tokens

GPT-4.5
Input
$75.00
Output
$150.00
Grok 4
Input
$3.00
25× cheaper
Output
$15.00
10× cheaper

Grok 4 is cheaper on both: 25× input, 10× output.

Writing DNA

Style Comparison

Similarity
55%

Grok 4 uses 59.8x more emoji

GPT-4.5
Grok 4
63%Vocabulary56%
16wSentence Length18w
0.57Hedging0.65
4.7Bold2.4
6.4Lists2.4
0.00Emoji0.60
1.30Headings0.73
0.54Transitions0.06
Based on 11 + 26 text responses
Research

What we learned reading every model

FAQ

Common questions

GPT-4.5 is developed by OpenAI while Grok 4 is developed by xAI. GPT-4.5 has a 128K token context window vs Grok 4's 256K. You can compare their actual outputs across 24 challenges on Rival to see how they differ in practice.

It depends on your use case. GPT-4.5 and Grok 4 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 24 challenges so you can judge which fits your needs best.

GPT-4.5 costs $75/M input tokens and Grok 4 costs $3/M input tokens. Grok 4 is $72.00/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-4.5 and Grok 4 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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