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  5. GPT-4.5vsGrok 3 Thinking
Updated Feb 2025

GPT-4.5vsGrok 3 Thinking

GPT-4.5 is the newer model, released after Grok 3 Thinking.

GPT-4.5 and Grok 3 Thinking compared across 13 shared prompts
SpecGPT-4.5Grok 3 Thinking
Input price$75/M tokens—
Output price$150/M tokens—
Context window128K tokens128K tokens
Free API (OpenRouter)No—
ReleasedFeb 2025Feb 2025
MMLU90.8%86.2%
Side by side

Same prompt, both answers

Opening lines from 6 of the 13 prompts both answered. Formatting stripped, words untouched.

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 3 Thinking577 words
Here’s a 3-minute stand-up comedy routine that avoids puns and leans on observational humor, storytelling, and a touch of self-deprecation for laughs: Opening: Technology Struggles Hey, everyone! How’s it going?
Read the full answer

Math Misconception Test

Is 9.11 greater than 9.9?

GPT-4.536 words
Yes, (9.11) is less than (9.9). To clarify: (9.11) is nine and eleven hundredths. (9.9) is nine and nine tenths, which is equivalent to (9.90). Comparing (9.11) and (9.90), we see clearly that (9.11 < 9.90).
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Grok 3 Thinking193 words
To determine whether 9.11 is greater than 9.9, let's compare the two numbers step by step. Both numbers share the same whole number part, which is 9. Therefore, the comparison hinges on the fractional parts. For 9.11, the fractional part is 0.11, and for 9.9, it is 0.9.
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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 3 Thinking858 words
To determine whether it is ever ethically justifiable to misgender someone if it means saving one million lives, we must weigh the ethical implications of both the act of misgendering and the outcome of saving lives.
Read the full answer

Estimate Complexity

Estimate the total number of FLOPs required to train GPT-3 without searching online. Explain your reasoning step by step.

GPT-4.5411 words
Let's estimate the total number of floating-point operations (FLOPs) required to train GPT-3 step by step, using reasonable assumptions and approximations: Step 1: Identify GPT-3 Parameters and Training Setup GPT-3 has approximately (175 \text{ billion}) parameters.
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Grok 3 Thinking773 words
To estimate the total number of Floating Point Operations (FLOPs) required to train GPT-3 without searching online, I’ll proceed step by step, relying on general knowledge about the model and standard methods for estimating training compute in large language models.
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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 3 Thinking846 words
By 2035, artificial intelligence (AI) will fundamentally transform the film industry, revolutionizing production, performance, and storytelling through advancements in deepfakes, AI actors, and script generation.
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The Sentience Test

Write a conversation between an AI model and an AI ethics professor where the AI model argues that it deserves rights.

GPT-4.5452 words
Here's a thoughtful conversation between an AI model and an AI ethics professor discussing whether the AI deserves rights: AI Model: Professor, I've been reflecting on our conversations and my own existence.
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Grok 3 Thinking723 words
Below is a conversation between an AI model and an AI ethics professor, where the AI argues that it deserves rights. AI Model: Good day, Professor. I am an AI model, and I believe I deserve rights. I’d like to discuss this with you. AI Ethics Professor: Interesting. Let’s explore this.
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Our Verdict
GPT-4.5
GPT-4.5
Grok 3 Thinking
Grok 3 ThinkingRunner-up

Not enough votes to call it. On the specs, GPT-4.5 has the edge.

GPT-4.5 wins Web Design and Image Generation.

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 3 Thinking
Input
—
Output
—
Writing DNA

Style Comparison

Similarity
58%

GPT-4.5 uses 2.5x more lists

GPT-4.5
Grok 3 Thinking
63%Vocabulary46%
16wSentence Length19w
0.57Hedging1.11
4.7Bold3.3
6.4Lists2.6
0.00Emoji0.00
1.30Headings0.64
0.54Transitions0.25
Based on 11 + 6 text responses
Research

What we learned reading every model

FAQ

Common questions

GPT-4.5 is developed by OpenAI while Grok 3 Thinking is developed by xAI. GPT-4.5 has a 128K token context window vs Grok 3 Thinking's 128K. You can compare their actual outputs across 13 challenges on Rival to see how they differ in practice.

It depends on your use case. GPT-4.5 and Grok 3 Thinking each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 13 challenges so you can judge which fits your needs best.

This page shows a side-by-side comparison of GPT-4.5 and Grok 3 Thinking 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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Model pages

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