Updated Aug 5, 2025

Our Verdict

Claude Opus 4Winner

GPT OSS 20BRunner-up

Pick Claude Opus 4. In 2 blind votes, Claude Opus 4 wins 100% of the time. That's not luck.

Claude Opus 4 particularly excels in Web Design. GPT OSS 20B is 750x cheaper per token — worth considering if cost matters.

Clear winner

Writing DNA

Style Comparison

Similarity

100%

Claude Opus 4 uses 3.6x more sentence length

GPT OSS 20B

Claude Opus 4

54%Vocabulary64%

17wSentence Length62w

0.26Hedging0.52

5.9Bold4.4

3.3Lists9.1

0.10Emoji0.11

0.75Headings1.87

0.32Transitions0.27

Based on 21 + 16 text responses

vs

Ask them anything yourself

GPT OSS 20B

Claude Opus 4

279 AI models invented the same fake scientist.

We read every word. 250 models. 2.14 million words. This is what we found.

AI Hallucination Index 2026

Free preview13 of 58 slides

Download the free preview or get all 58 slides for $49

FAQ

Common questions

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GPT OSS 20B vs MiniMax M2.5New provider

Claude Opus 4 vs Pony AlphaNew provider

GPT OSS 20B vs Claude Sonnet 4Cross-provider

GPT OSS 20BvsClaude Opus 4

35 fights queued

Why GPT OSS 20B?

750x cheaper overall$0.02/M in · $0.10/M out

3 months newerAug 2025

Why Claude Opus 4?

1.5x more context200K

GPT OSS 20BClaude Opus 4

Input price

$0.02/M

$15.00/M

Output price

$0.10/M

$75.00/M

Context

131K

200K

Released

Aug 2025

May 2025

Favorites

GPT OSS 20BClaude Opus 4

Movie

—

Arrival

Arrival

Album

—

The Dark Side of the Moon

The Dark Side of the Moon

Book

—

Cien años de soledad

Cien años de soledad

Gabriel García Márquez

City

—

Istanbul

Game

—

Portal 2

Portal 2

Shooter, Puzzle4.6

12 / 35

01

Logic Puzzlereasoning

Tests an AI's ability to solve a simple but potentially confusing logic puzzle

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025text

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025text

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

2 / 35

02

Stochastic Consistency Testanalysis

Tests an AI's randomness and creativity

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025text

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025text

Here are 5 jokes:

Why don't scientists trust atoms? Because they make up everything!
What do you call a bear with no teeth? A gummy bear!
Why did the scarecrow win an award? He was outstanding in his field!
What do you call a fake noodle? An impasta!
Why don't eggs tell jokes? They'd crack up!

All 5 jokes are unique - each one has a different setup and punchline, covering different topics (atoms/scie nce, bears, scarecrows, pasta, and eggs).

Try this prompt

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3 / 35

03

SVG Layout Challengeimage generation

Tests an AI's ability to generate vector graphics

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025svg

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025svg

Try this prompt

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4 / 35

04

Xbox Controller SVG Artimage generation

Tests an AI's ability to create detailed SVG illustrations of gaming hardware

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025svg

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025svg

Try this prompt

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5 / 35

05

Generate a Stand-Up Routineconversation

Tests an AI's humor and creative writing ability

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025text

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025text

"Modern Life is Weird"

[Walk on stage]

You know what's crazy about being an adult? Nobody tells you that half of it is just googling things you're too embarrassed to ask real people. Last week I googled "is it normal for my knee to sound like bubble wrap? " The answer was either "yes, totally fine" or "you have six weeks to live." Thanks, internet!

[Pause]

I went to the doctor about it. You know you're getting old when your doctor looks like they should be asking YOU for ID to buy alcohol. This kid walks in with a stethoscope, and I'm like, "Did you just graduate... fr om middle school?"

But here's what really gets me – why do we act completely insane at the doctor's office? They ask, "How much do you drink?" and suddenly I'm doing calculus in my head. "Well, let's see, carry the one... I have a glas s of wine with dinner." Yeah, a glass. It's just a really big glass. It's a vase, actually. I drink wine fro m a vase.

[Mime drinking from large container]

And don't get me started on grocery shopping. Why do I need a PhD to buy shampoo? There's moisturizing, volu mizing, clarifying, fortifying... I just want my hair to be clean! I don't need it to solve my emotional pro blems!

Plus, self-checkout is a trap. They put you in charge of scanning your own groceries like you work there. Th en the machine starts screaming "UNEXPECTED ITEM IN BAGGING AREA!" Yeah, it's unexpected because I don't wor k here! I'm doing my best, robot!

[Pause for effect]

The worst part is when you're buying embarrassing things. Last week I had toilet paper, ice cream, and cat f ood. The machine froze, and the teenage employee had to come over. He looked at my items and I could see him thinking, "This person's having a rough week."

[Shrug]

Speaking of technology, my phone knows too much about me. It autocorrects "running late" before I even type it because that's apparently my catchphrase now. My maps app just assumes I'm lost. It doesn't even wait for me to ask for directions anymore. I'll be sitting on my couch and it's like, "Turn right to get to your kit chen."

And what's with password requirements these days? "Must contain uppercase, lowercase, numbers, symbols, the blood of your firstborn, and a haiku about your childhood fears." Then they're like, "Don't write it down!" Where am I supposed to store this information? I can't remember why I walked into a room!

[Pace across stage]

You know what else nobody prepared me for? How excited I'd get about cancelled plans. Someone texts "Hey, ca n we raincheck?" and I'm already in my pajamas like "Oh no! What a shame! I was so looking forward to puttin g on real pants!"

Because going out now requires preparation. I need three business days' notice. I need to charge my social b attery. I need to practice conversation topics. Remember when we could just... show up places?

[Final beat]

The truth is, we're all just walking around pretending we know what we're doing. But at least we're all conf used together. And hey, if you ever see someone at the store at 10 PM buying wine in a box and googling "why does my back hurt when I breathe?" – just give them a nod. We're all in this together.

[Pause]

Thank you, you've been a wonderful audience! Don't forget to validate your parking – unlike my life choices!

[Exit]

Try this prompt

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6 / 35

06

Pokémon Battle UI Recreationweb design

Recreate an interactive, nostalgic Pokémon battle UI in a single HTML file.

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025website

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025website

Try this prompt

Vote

Sponsored

7 / 35

07

Three.js 3D Gameweb design

Create a 3D building and driving game in a single self-contained HTML file using Three.js. Tests an AI's ability to combine 3D graphics, game logic, and UI interactions on the web.

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025html

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025html

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

8 / 35

08

Mario Level UI Recreationweb design

Recreate an interactive, classic Mario level in a single HTML file.

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025website

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Claude Opus 4

Claude Opus 4

Anthropic · May 2025website

Try this prompt

Vote

9 / 35

09

Linear App Cloneweb design

Tests an AI's ability to replicate an existing UI with Tailwind CSS

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025website

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025website

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

10 / 35

10

Interactive Catan Boardweb design

Tests an AI's ability to create interactive web elements

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025website

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025website

Try this prompt

Vote

11 / 35

11

World Map SVGimage generation

Tests an AI's ability to create a detailed world map in SVG format

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025svg

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025svg

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

12 / 35

12

Random Tailwind Webappweb design

Generate a single-page, self-contained HTML webapp using Tailwind CSS for a randomly chosen category/industry/niche.

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025website

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Claude Opus 4

Claude Opus 4

Anthropic · May 2025website

Nothing here. The model returned empty. We stared at it for a while.

Try this prompt

Vote

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