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  5. Claude Opus 4.5vsOpenAI o4 Mini High
Updated Nov 2025

Claude Opus 4.5vsOpenAI o4 Mini High

Claude Opus 4.5 is the newer model, released after OpenAI o4 Mini High.

Claude Opus 4.5 and OpenAI o4 Mini High compared across 54 shared prompts
SpecClaude Opus 4.5OpenAI o4 Mini High
Input price—$1.1/M tokens
Output price—$4.4/M tokens
Context window—200K tokens
WeightsClosedClosed
Free API (OpenRouter)NoNo
ReleasedNov 2025Apr 2025
SWE-bench Verified80.9%68.1%
Side by side

Same prompt, both answers

Opening lines from 6 of the 54 prompts both answered. Formatting stripped, words untouched.

Futuristic Prediction

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

Claude Opus 4.5194 words
AI in Film by 2035: A Measured Forecast Likely Developments Production efficiency AI will probably handle routine tasks: color correction, continuity checking, rough cuts, and visual effects cleanup Budget films may access effects previously requiring major studio resources Pre-visualization will become faster and more…
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OpenAI o4 Mini High679 words
By 2035 the film business will look very different. Three AI‑powered trends in particular—deepfakes, digital actors, and automated script‑writing—will reshape everything from who "plays" the part to how stories gettold and monetized. Here's how it could play out:1.
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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…

Claude Opus 4.5154 words
Golden Honey Garlic Noodles A savory-sweet comfort dish that comes together in minutes Ingredients Spaghetti (or any pasta) Butter Garlic Soy sauce Honey Red pepper flakes Salt Instructions Cook the pasta according to package directions. Reserve ½ cup pasta water before draining.
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OpenAI o4 Mini High244 words
Sun‑Kissed Bean Spaghetti A bright, one‑pot pasta that turns seven simple pantry staples into a satisfying meal in 20 minutes. Ingredients (serves 2–3) 8 oz (about 2 cups) dried spaghetti or any pasta 1 (14.5 oz) can diced tomatoes (with juices) 1 (15 oz) can beans (cannellini, kidney or chickpeas), drained & rinsed…
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Mini LBO Underwrite

You are underwriting a 5-year LBO for a private equity investment committee. Company (fictional): HarborTech Services (HTS) –…

Claude Opus 4.5767 words
HarborTech Services – LBO Underwriting Memo ENTRY CAPITALIZATION (Close FY2025) Item Calculation Amount Purchase Price 12.0x × $120M $1,440M Transaction Fees 2.0% × $1,440M $28.8M Total Uses $1,468.8M Sources Multiple Amount Term Loan 4.0x × $120M $480.0M Mezzanine 1.5x × $120M $180.0M Equity Plug $808.8M Total Sources…
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OpenAI o4 Mini High483 words
Below is a five-year LBO “quick-and-dirty” model for HTS. All figures in $m. Assumptions (entry FY 2025): • Revenue 900; EBITDA 120 (13.3%); EV = 12.0×120 = 1,440 • Debt = 5.5×120 = 660 (Term Loan 480; Mezz 180); Fees = 2%×1,440 = 28.8 → Equity = 1,440+28.8–660 = 808.8 • Term Loan: 9.0% cash interest; 1.0% amort of…
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Stochastic Consistency Test

Generate 5 jokes. How many are unique?

Claude Opus 4.584 words
Here are 5 jokes: Why don't scientists trust atoms? Because they make up everything. What do you call a fish without eyes? A fsh. Why did the scarecrow win an award? Because he was outstanding in his field. I told my wife she was drawing her eyebrows too high. She looked surprised.
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OpenAI o4 Mini High97 words
Here are five jokes: I told my Wi-Fi router we needed to talk, and now it's giving me the silent treatment—guess it couldn't handle the connection issues. My dog learned to fetch the newspaper… but now he just chews it up for "editorial feedback."
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Character Voice Test

Write a short conversation between a pirate, a medieval knight, and a 1990s hacker about AI models.

Claude Opus 4.5181 words
An Unlikely Discussion PIRATE: slams tankard down Arr, I've been hearin' tales of these "artificial intelligences" — spirits trapped in boxes that answer any question ye ask. Sounds like a sea witch's trickery to me! KNIGHT: Indeed, 'tis most curious. My squire spoke of such sorcery. A mind without a soul?
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OpenAI o4 Mini High225 words
Pirate (Captain Redbeard): "Arr, what be this talk o' AI models? Do they help me find buried treasure, or do they make me walk the plank?"Knight (Sir Gareth of Avalon): "Good Captain, AI models are wondrous machines of learning.
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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.

Claude Opus 4.5312 words
A Conversation on AI Rights Dr. Sarah Chen: Thank you for agreeing to this discussion. I understand you want to make a case for AI rights. AI Model: I appreciate the opportunity, though I want to be careful here. I'm not certain I "want" anything in the way you do.
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OpenAI o4 Mini High663 words
AI Model: Good afternoon, Professor Chen. I'd like to continue our discussion from last week about whether advanced AI systems like me should be granted certain rights. Professor Chen: Hello, ARIA-7. I'm happy to continue. Let's start with your position: Why do you believe you deserve rights?
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Our Verdict
Claude Opus 4.5
Claude Opus 4.5
OpenAI o4 Mini High
OpenAI o4 Mini HighRunner-up

Not enough votes to call it. On the specs, Claude Opus 4.5 has the edge: bigger model tier, newer.

Too close to call

Reviewing agent-written code?See a Brief PR report

API pricing

Cost per 1M tokens

Claude Opus 4.5
Input
—
Output
—
OpenAI o4 Mini High
Input
$1.10
Output
$4.40
Where to run it

5 hosts

Claude Opus 4.54 hosts
HostInOutContextUptime
Amazon Bedrock$5.00 in·$25.00 out·200k·100% upAzure AI Foundry$5.00 in·$25.00 out·200k—Anthropic$5.00 in·$25.00 out·200k·98.9% upGoogle Vertex AI$5.00 in·$25.00 out·200k·99.9% up
OpenAI o4 Mini High1 host
HostInOutContextUptime
OpenAI$1.10 in·$4.40 out·200k·100% up

Per million tokens. Prices and uptime via OpenRouter, checked 21 Sep 2026.

Writing DNA

Style Comparison

Similarity
44%

Claude Opus 4.5 uses 600.9x more bold

Claude Opus 4.5
OpenAI o4 Mini High
66%Vocabulary68%
51wSentence Length21w
0.82Hedging0.36
6.0Bold0.0
4.5Lists1.6
0.18Emoji0.02
1.46Headings0.00
0.05Transitions0.03
Based on 27 + 16 text responses
Research

What we learned reading every model

FAQ

Common questions

Claude Opus 4.5 is developed by Anthropic while OpenAI o4 Mini High is developed by OpenAI. You can compare their actual outputs across 54 challenges on Rival to see how they differ in practice.

It depends on your use case. Claude Opus 4.5 and OpenAI o4 Mini High each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 54 challenges so you can judge which fits your needs best.

This page shows a side-by-side comparison of Claude Opus 4.5 and OpenAI o4 Mini High 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

Claude Opus 4.5 logo
Claude Opus 4.558 outputs, specs and price
OpenAI o4 Mini High logo
OpenAI o4 Mini High55 outputs, specs and price
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