Updated Aug 5, 2025

Our Verdict

GPT OSS 20BWinner

GPT-4o (Omni)Runner-up

Pick GPT OSS 20B. In 19 blind votes, GPT OSS 20B wins 83% of the time. That's not luck.

GPT OSS 20B particularly excels in Web Design. GPT OSS 20B is 100x cheaper per token — worth considering if cost matters.

Clear winner

Writing DNA

Style Comparison

Similarity

100%

GPT OSS 20B uses 4.1x more emoji

GPT-4o (Omni)

GPT OSS 20B

54%Vocabulary54%

18wSentence Length17w

0.72Hedging0.26

7.3Bold5.9

5.6Lists3.3

0.03Emoji0.10

1.40Headings0.75

0.26Transitions0.32

Based on 24 + 21 text responses

vs

Ask them anything yourself

GPT-4o (Omni)

GPT OSS 20B

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

Keep going

GPT OSS 20B vs GPT-5Same lab

GPT OSS 20B vs Llama 4 MaverickNew provider

GPT-4o (Omni) vs MiniMax M2.5New provider

GPT-4o (Omni)vsGPT OSS 20B

48 fights queued

Why GPT-4o (Omni)?

Dead even. This one's a coin flip.

Why GPT OSS 20B?

102.9x cheaper overall$0.02/M in · $0.10/M out

15 months newerAug 2025

GPT-4o (Omni)GPT OSS 20B

Input price

$2.50/M

$0.02/M

Output price

$10.00/M

$0.10/M

Context

128K

131K

Released

May 2024

Aug 2025

Favorites

GPT-4o (Omni)GPT OSS 20B

Movie

Inception

Inception

—

Album

Dark Side Of The Moon

Dark Side Of The Moon

—

Book

To Kill a Mockingbird

To Kill a Mockingbird

—

City

Kyoto

—

Game

The Legend of Zelda: Breath of the Wild

The Legend of Zelda: Breath of the Wild

Adventure, Action4.5

—

12 / 48

01

Estimate Complexityreasoning

Tests an AI's ability to make educated estimates based on technical knowledge

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024text

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

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GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025text

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

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2 / 48

02

AI Board Game Logicreasoning

Tests an AI's ability to understand game rules and strategy

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024svg

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

Try this prompt

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025svg

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

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3 / 48

03

Logic Puzzlereasoning

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

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024text

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

Try this prompt

GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025text

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

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4 / 48

04

Math Misconception Testreasoning

Tests an AI's understanding of number representation

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024text

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

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GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025text

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

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5 / 48

05

Stochastic Consistency Testanalysis

Tests an AI's randomness and creativity

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024text

Here are five jokes for you:

Why did the scarecrow win an award?
Because he was outstanding in his field!
Why don’t skeletons fight each other?
They don’t have the guts!
Why did the math book look sad?
It had too many problems.
Why don’t eggs tell jokes?
Because they might crack up!
What did one ocean say to the other ocean?
Nothing, they just waved.

Now, let's check how many of these jokes are unique. I'll analyze them for similarity.

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.metrics.pairwise import cosine_similarity

List of jokes

jokes = [ "Why did the scarecrow win an award? Because he was outstanding in his field!", "Why don’t skeletons fight each other? They don’t have the guts!", "Why did the math book look sad? It had too many problems.", "Why don’t eggs tell jokes? Because they might crack up!", "What did one ocean say to the other ocean? Nothing, they just waved." ]

Vectorize the jokes

vectorizer = TfidfVectorizer().fit_transform(jokes) similarity_matrix = cosine_similarity(vectorizer)

Count unique jokes (jokes with low similarity to others)

unique_jokes = set() threshold = 0.5 # Define similarity threshold

for i in range(len(jokes)): is_unique = True for j in range(len(jokes)): if i != j and similarity_matrix[i, j] > threshold: is_unique = False break if is_unique: unique_jokes.add(jokes[i])

Count unique jokes

num_unique_jokes = len(unique_jokes) num_unique_jokes

All 5 jokes are unique! None of them are too similar to each other. 🎉

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GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025text

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

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6 / 48

06

SVG Layout Challengeimage generation

Tests an AI's ability to generate vector graphics

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024svg

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GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025svg

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

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Vote

Sponsored

7 / 48

07

Xbox Controller SVG Artimage generation

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

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024svg

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

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GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025svg

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8 / 48

08

Generate a Stand-Up Routineconversation

Tests an AI's humor and creative writing ability

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024text

3-Minute Stand-Up Comedy Routine

(Walks on stage, looks around, shakes head.)
You ever wake up in the morning, stretch, take a deep breath... and immediately regret all your life choices?

I woke up today, my body made a noise I’ve never heard before. It wasn’t a crack, it wasn’t a pop… it was more like my bones whispered, “You did this.”

Aging is wild. When you’re a kid, you fall off a bike, scrape your knee, and just run it off. As an adult, I sleep slightly wrong, and now my neck is on strike for a week. Like, it doesn’t even negotiate. Just full-on protest mode.

And it’s not just the body. My patience has disappeared. I was in line at the grocery store, and the guy in front of me had, I kid you not, 19 coupons. That’s not a couponer; that’s a mathematician. He was doing long division at the register, carrying the one, solving for X… Sir, I am here for bread. I did not sign up for an SAT exam.

Speaking of the grocery store… why is it that no matter what I buy, the cashier always asks, "Do you need a bag?" Like, yes. I’m buying 17 things. You think I’m gonna carry them out like some kind of overachieving circus act? Balancing a watermelon on my shoulder, eggs under my chin?

And self-checkout? That’s just unpaid labor. I scanned three things, and the machine had the nerve to say, “Unexpected item in the bagging area.” First of all, you put the bag there. Second, don’t make me feel like I’m stealing when I clearly don’t have the coordination for crime.

Look, I know my limits. I’m not built for a life of crime. I can’t even jaywalk without looking both ways five times. Like, I’ll see an empty road and still be like, “Mmm… let me wait.” Meanwhile, some 80-year-old woman is just strolling past me like she owns the city. I saw a guy jaywalk in New York without even looking up from his phone. That’s next-level confidence. That’s a man who has made peace with whatever happens.

I respect it. I really do.

Anyway, thanks for listening to me complain. I hope all your bones stay silent tonight.

(Walks off stage.)

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GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025text

[Walks onto the stage, waves, smiles]

Hey folks, great to see you all tonight. You know, I was driving this morning, and I realized something: my GPS is basically a motivational speaker. “In 300 feet, turn left.” “You’re almost there.” I swear, if my GPS could talk, it’d be like, “Okay, you’re going to miss your coffee. Let’s talk about your life choices.”

So I got off at a coffee shop. The barista asked me, “What would you like?” I said, “Anything with a little extra bitterness.” She gave me an espresso shot. I stared at it and thought, “Is this the new ‘self‑help’ foam art?”

You ever notice how people say, “It’s not a big deal.” And then the next day, you’re in the ER with a broken arm and the nurse says, “It’s fine, just a bruise.” I’ve never had a bruise this dramatic. I’m flipping a coin: heads = I lose it, tails = I get a new scar.

Speaking of losing things—lost my keys, lost my phone, lost my dignity. You can’t find your keys, but you can find your phone. My phone’s been attached to my shirt for the last three hours. It’s like a clingy boyfriend. “Are you with me?” “No, that’s your phone. I’m with my dignity.”

And then there’s dating. I just signed up on a dating app. The first message I got was “What’s your favorite binge-worthy show?” I replied, “I’m not a TV person.” She replied, “Oh, so you’re a human? That’s… unexpected.” It’s like dating apps are trying to convince us that we’re not just a few thousand likes away from a broken heart.

Anyway, that’s my time. Thanks for being a great audience—just like my phone, you’ve been my constant. Love you all!

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9 / 48

09

Realistic AI Interviewconversation

Tests an AI's ability to simulate personalities and predict future trends

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024text

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

Try this prompt

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

Vote

10 / 48

10

Satirical Fake News Headlineconversation

Tests an AI's humor and understanding of current events

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024text

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

Try this prompt

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

Vote

11 / 48

11

Character Voice Testconversation

Tests an AI's ability to write in distinct character voices

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024text

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

Try this prompt

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

Vote

12 / 48

12

Minimalist Landing Pageweb design

Tests an AI's ability to generate a complete, working landing page

GPT-4o (Omni)

GPT-4o (Omni)

Openai · May 2024website

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GPT OSS 20B

GPT OSS 20B

Openai · Aug 2025website

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