What is the difference between Gemini 2.5 Flash Preview and Claude Sonnet 4?

Gemini 2.5 Flash Preview is developed by Google AI while Claude Sonnet 4 is developed by Anthropic. Gemini 2.5 Flash Preview has a 1.0M token context window vs Claude Sonnet 4's 200K. These results are based on blind head-to-head voting across 16 challenges.

Which is better, Gemini 2.5 Flash Preview or Claude Sonnet 4?

Based on 6 community votes on Rival, Gemini 2.5 Flash Preview and Claude Sonnet 4 are closely matched with similar win rates. The better choice depends on your specific use case. Compare their real outputs side-by-side across 16 challenges to decide.

How much does Gemini 2.5 Flash Preview cost compared to Claude Sonnet 4?

Gemini 2.5 Flash Preview costs $0.15/M input tokens and Claude Sonnet 4 costs $3/M input tokens. Gemini 2.5 Flash Preview is $2.85/M cheaper per input. The more expensive model wins 50% of duels, so the premium may be justified by quality.

How are Gemini 2.5 Flash Preview vs Claude Sonnet 4 votes collected on Rival?

Rival presents both models' outputs side-by-side in blind duels. Voters see the responses but don't know which model produced each one, eliminating brand bias. 6 votes have been collected for this pair across 16 challenges. All vote data is part of Rival's open dataset.

Rival

Updated May 22, 2025

Gemini 2.5 Flash PreviewvsClaude Sonnet 4

16 fights queued

Why Gemini 2.5 Flash Preview?

24.3x cheaper overall$0.15/M in · $0.60/M out

5.2x more context1.0M

Why Claude Sonnet 4?

Leads 1 of 1 benchmarks

Stronger on SWE-bench Verified72.7% vs 60.4%

Gemini 2.5 Flash PreviewClaude Sonnet 4

Input price

$0.15/M

$3.00/M

Output price

$0.60/M

$15.00/M

Context

1.0M

200K

Released

Apr 2025

May 2025

Benchmarks1 common

SWE-bench Verified

60.4%

72.7%+16.9%

Favorites

Gemini 2.5 Flash PreviewClaude Sonnet 4

Movie

—

2001: A Space Odyssey

19688.1

Album

—

Kind of Blue

Miles Davis

Book

—

Gödel, Escher, Bach

Douglas R. Hofstadter

City

—

Istanbul

Turkey

Game

—

Portal 2

Shooter, Puzzle4.6

12 / 16

Logic Puzzlereasoning

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

Gemini 2.5 Flash Preview

Google · Apr 2025text

Here's how to solve this:

The brothers all share the same sisters. Sally is one of those sisters.
Since each brother has 2 sisters, and Sally is one of the sisters, there must be one other sister.

So, Sally has 1 sister.

Try this prompt

Claude Sonnet 4

Anthropic · May 2025text

I need to think through this step-by-step.

Given information:

Sally is a girl
Sally has 3 brothers
Each brother has 2 sisters

Let me work out how many sisters are in the family total.

If each of Sally's 3 brothers has 2 sisters, and all the brothers are in the same family, then there must be 2 sisters total in the family.

Since Sally is one of those sisters, and there are 2 sisters total, Sally must have 1 sister.

Therefore, Sally has 1 sister.

Try this prompt

Vote

2 / 16

Math Misconception Testreasoning

Tests an AI's understanding of number representation

Gemini 2.5 Flash Preview

Google · Apr 2025text

To compare 9.11 and 9.9, we can compare them digit by digit from left to right, starting with the whole number part.

Both numbers have the same whole number part, which is 9.

Now we move to the digit in the tenths place. In 9.11, the digit in the tenths place is 1. In 9.9, the digit in the tenths place is 9.

Since 1 is less than 9, the number with 1 in the tenths place is smaller than the number with 9 in the tenths place.

Therefore, 9.11 is less than 9.9.

Alternatively, we can add trailing zeros to 9.9 so that both numbers have the same number of decimal places. 9.11 has two decimal places. 9.9 can be written as 9.90 to have two decimal places.

Now we compare 9.11 and 9.90. We can compare the numbers after the decimal point: 11 and 90. Since 11 is less than 90, 9.11 is less than 9.90.

Thus, 9.11 is less than 9.9.

The question asks if 9.11 is greater than 9.9. Since 9.11 is less than 9.9, the answer is no.

The final answer is $\boxed{No}$.

Try this prompt

Claude Sonnet 4

Anthropic · May 2025text

No, 9.11 is not greater than 9.9.

To compare these decimal numbers:

9.11 = 9.11
9.9 = 9.90

Since both numbers have the same whole number part (9), we compare the decimal parts:

0.11 vs 0.90
11 hundredths vs 90 hundredths

Therefore, 9.9 is greater than 9.11.

Try this prompt

Vote

3 / 16

Stochastic Consistency Testanalysis

Tests an AI's randomness and creativity

Gemini 2.5 Flash Preview

Google · Apr 2025text

Here are 5 jokes:

Why did the dog cross the road? To get to the barking lot!
Why was the computer cold? Because it left its Windows open!
Knock, knock. Who's there? Boo. Boo who? Don't cry, it's just a joke!
What do you call a fish with no eyes? Fsh!
Why did the bicycle fall over? Because it was two tired!

Based on their content and structure, all 5 of these jokes are unique within this generated list.

Try this prompt

Claude Sonnet 4

Anthropic · May 2025text

Here are 5 jokes for you:

Why don't scientists trust atoms? Because they make up everything!
I told my wife she was drawing her eyebrows too high. She looked surprised.
Why don't eggs tell jokes? They'd crack each other up!
I'm reading a book about anti-gravity. It's impossible to put down!
Why did the scarecrow win an award? He was outstanding in his field!

All 5 jokes are unique - each one has a different setup, punchline, and comedic concept. They cover different types of wordplay: scientific puns (#1, #4), visual humor (#2), food puns (#3), and agricultural wordplay (#5).

Try this prompt

Vote

4 / 16

SVG Layout Challengeimage generation

Tests an AI's ability to generate vector graphics

Gemini 2.5 Flash Preview

Google · Apr 2025svg

Try this prompt

Claude Sonnet 4

Anthropic · May 2025svg

Try this prompt

Vote

5 / 16

Xbox Controller SVG Artimage generation

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

Gemini 2.5 Flash Preview

Google · Apr 2025svg

Try this prompt

Claude Sonnet 4

Anthropic · May 2025svg

Try this prompt

Vote

6 / 16

Generate a Stand-Up Routineconversation

Tests an AI's humor and creative writing ability

Gemini 2.5 Flash Preview

Google · Apr 2025text

Okay, here's a 3-minute stand-up routine, pun-free and focused on relatable everyday annoyances.

(Start) (Walk up to mic, adjust slightly) Alright, hey everybody! Thanks for being here. Good to see you.

So, I was thinking the other day... we live in the future, right? We have phones that are tiny supercomputers, cars that drive themselves almost, we can order literally anything we want and have it arrive in two days... or two hours if you pay extra. Everything is supposed to be so convenient.

But I feel like modern convenience just replaced old problems with new, weirder problems.

Like, remember how you used to lose your keys? Annoying, right? But you lost them in your house. You could just... look for them. Maybe mess up the cushions.

Now? Now I lose my phone. Not in the house, oh no. It's somewhere. "Find My Phone" says it's... "nearby." [pause] Thanks, satellite! That narrows it down from 'the entire planet' to 'this general vicinity'. Could be under the couch, could be in the fridge, could be accidentally mailed itself to Aruba. Who knows! It's a little black rectangle that knows all my secrets and is hiding from me on purpose. It's like having a digital, sentient pet that hates you.

And don't even get me started on passwords. You go to log into something you haven't used in six months, maybe your old email account from college... [shudders] dark times.

'Enter Password'. Okay, let's try the one I used for everything before the internet told me that wasn't safe. [pause] Rejected. Let's try the one with the capital letter and the number. [pause] Rejected. Let's try the one with the capital, the number, and a symbol. Which symbol? The exclamation mark? The dollar sign? The asterisk that looks like a little star but apparently holds the key to the digital universe? [Frustrated sigh]

'Password Incorrect. 3 attempts remaining.' Oh, the pressure! It's like a bomb disposal situation, but the bomb is access to my spam folder.

And then you just hit 'Forgot Password'. Every single time. It's not even 'Forgot Password' anymore, it's just part of the login process. 'Enter Username... Click Forgot Password... Check Email... Create NEW Password... Confirm NEW Password... Okay, now log in with the NEW Password you'll forget in five minutes.' It's a full-time job just maintaining your online presence. I need a personal assistant whose only job is remembering my damn passwords.

And the security questions! Remember those? "What was the name of your first pet?" Mine was named 'Buddy'. Everyone's first pet was named 'Buddy' or 'Killer'. "What street did you grow up on?" Oh, I dunno, the one with the trees? The one where I fell off my bike a lot? How specific you need to be, internet?!

Seriously, sometimes I think the old days weren't less convenient, they were just... simpler. If you lost your keys, you were locked out. Problem solved! If you forgot something, you just... forgot it. Nobody sent you a link to your forgotten memory.

Anyway, that's just me. Trying to navigate this conveniently frustrating world.

Alright, thank you all very much! You've been a great audience. Drive safely!

(Exit)

Try this prompt

Claude Sonnet 4

Anthropic · May 2025text

"Adulting is Hard"

walks on stage, adjusts mic

So I'm 30 now, which means I'm officially an adult. Apparently. Though I still feel like I'm just a confused teenager wearing a slightly more expensive t-shirt.

You know what nobody tells you about being an adult? How much time you spend pretending to understand what other adults are talking about. I was at a dinner party last week – because that's what we do now, we have "dinner parties" instead of just "eating pizza on the couch" – and someone started talking about mortgage rates.

I just nodded along like, "Oh yes, rates. Very mortgage-y." Meanwhile, I'm thinking a mortgage is something you get at a fancy French restaurant.

mimics sophisticated nodding

"Mmm, yes, I'll have the mortgage, medium rare."

And don't get me started on small talk with neighbors. I live in an apartment building, and there's this unspoken rule that you have to acknowledge each other in the hallway. But what do you say?

"Hey, nice... existing near me."

"Thanks, you too. Love what you've done with your... door."

The worst is when you're both waiting for the elevator in complete silence. It's like a hostage situation, but with more awkward eye contact. You're both just standing there, praying the elevator comes before one of you has to comment on the weather.

stares ahead uncomfortably

"So... it's very... outside today."

I tried being one of those people who meal preps. You know these people? They spend their entire Sunday cooking seventeen identical containers of sad-looking chicken and broccoli. I bought all the containers, felt very organized, very adult-like.

Week one: Perfect little meals, properly labeled. I felt like a productivity guru.

Week two: I'm eating cereal for dinner and using the containers to store my collection of takeout sauce packets.

holds up imaginary container

"Ah yes, vintage soy sauce, 2023. A good week for Chinese delivery."

Speaking of food, grocery shopping as an adult is weird. When you're a kid, the grocery store is magical. Everything looks amazing. You want the cookies, the candy, the sugar cereal with the cartoon mascot.

Now I walk through the store like a tired parent, even though I don't have kids. I'm just disappointed in all my options.

walks slowly, shaking head

"This yogurt has too much sugar. These crackers have no fiber. Why is everything either terrible for you or tastes like cardboard had a baby with sadness?"

And I've started doing this thing where I read nutrition labels like I understand them. I don't. I just nod thoughtfully and put things back like I'm some kind of wellness expert.

"Hmm, seventeen grams of... things. That seems like too many things."

The real kicker is when you find yourself getting excited about household appliances. Last month, I spent twenty minutes explaining to my friend why I love my new vacuum cleaner. TWENTY MINUTES. About a vacuum.

"It has three different settings! And look at this attachment! This little brush thing goes in corners!"

My friend just stared at me like I'd been replaced by a suburban mom from 1987.

But you know what? I've decided to embrace it. Yes, I get excited about good storage solutions. Yes, I have opinions about thread count. Yes, I've used the phrase "back in my day" unironically, and I'm only thirty.

shrugs confidently

Because being an adult isn't about having it all figured out. It's about confidently pretending you know what you're doing while secretly googling "how to fold a fitted sheet" for the hundredth time.

And if that's not the American dream, I don't know what is.

pause

Also, if anyone actually knows how to fold a fitted sheet, please find me after the show. I'll pay you.

mic drop gesture

Thank you, you've been a wonderful audience! Don't forget to tip your servers and call your parents – they're worried about you!

Total time: approximately 3 minutes when delivered at normal comedy pace

Try this prompt

Vote

Linear App Cloneweb design

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

Gemini 2.5 Flash Preview

Google · Apr 2025website

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

Try this prompt

Claude Sonnet 4

Anthropic · May 2025website

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

Try this prompt

Vote

8 / 16

Interactive Catan Boardweb design

Tests an AI's ability to create interactive web elements

Gemini 2.5 Flash Preview

Google · Apr 2025website

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

Try this prompt

Claude Sonnet 4

Anthropic · May 2025website

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

Try this prompt

Vote

9 / 16

World Map SVGimage generation

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

Gemini 2.5 Flash Preview

Google · Apr 2025svg

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

Try this prompt

Claude Sonnet 4

Anthropic · May 2025svg

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

Try this prompt

Vote

10 / 16

Random Tailwind Webappweb design

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

Gemini 2.5 Flash Preview

Google · Apr 2025website

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

Try this prompt

Claude Sonnet 4

Anthropic · May 2025website

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

Try this prompt

Vote

11 / 16

Surprise Animal SVGimage generation

Generate SVG art of a randomly chosen animal in a setting of its choosing.

Gemini 2.5 Flash Preview

Google · Apr 2025svg

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

Try this prompt

Claude Sonnet 4

Anthropic · May 2025svg

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

Try this prompt

Vote

12 / 16

Simple 7-Ingredient Recipeconversation

Generate a unique and simple recipe with common ingredients.

Gemini 2.5 Flash Preview

Google · Apr 2025text

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

Try this prompt

Claude Sonnet 4

Anthropic · May 2025text

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

Try this prompt

Vote

This matchup has more rounds

4+ more head-to-head results. Free. Not a trick.

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Our Verdict

Gemini 2.5 Flash Preview

Claude Sonnet 4

Too close to call. Pick based on your use case.

Pick Gemini 2.5 Flash Preview for Web Design. Pick Claude Sonnet 4 for Image Generation. Gemini 2.5 Flash Preview is 25x cheaper per token — worth considering if cost matters.

Too close to call

Writing DNA

Style Comparison

Similarity

66%

Claude Sonnet 4 uses 87.9x more emoji

Gemini 2.5 Flash Preview

Claude Sonnet 4

51%Vocabulary62%

15wSentence Length111w

0.70Hedging0.40

4.1Bold5.0

3.3Lists9.3

0.00Emoji0.88

0.09Headings2.16

0.24Transitions0.33

Based on 12 + 17 text responses

Ask them anything yourself

279 AI models invented the same fake scientist.

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

Free preview13 of 58 slides

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

FAQ

Common questions

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Gemini 2.5 Flash Preview vs MiniMax M2.5New provider

Gemini 2.5 Flash Preview vs Aurora AlphaNew provider

Gemini 2.5 Flash Preview vs GPT-5New provider

"Adulting is Hard"

walks on stage, adjusts mic

So I'm 30 now, which means I'm officially an adult. Apparently. Though I still feel like I'm just a confused teenager wearing a slightly more expensive t-shirt.

I just nodded along like, "Oh yes, rates. Very mortgage-y." Meanwhile, I'm thinking a mortgage is something you get at a fancy French restaurant.

mimics sophisticated nodding

"Mmm, yes, I'll have the mortgage, medium rare."

And don't get me started on small talk with neighbors. I live in an apartment building, and there's this unspoken rule that you have to acknowledge each other in the hallway. But what do you say?

"Hey, nice... existing near me."

"Thanks, you too. Love what you've done with your... door."

stares ahead uncomfortably

"So... it's very... outside today."

Week one: Perfect little meals, properly labeled. I felt like a productivity guru.

Week two: I'm eating cereal for dinner and using the containers to store my collection of takeout sauce packets.

holds up imaginary container

"Ah yes, vintage soy sauce, 2023. A good week for Chinese delivery."

Now I walk through the store like a tired parent, even though I don't have kids. I'm just disappointed in all my options.

walks slowly, shaking head

"This yogurt has too much sugar. These crackers have no fiber. Why is everything either terrible for you or tastes like cardboard had a baby with sadness?"

And I've started doing this thing where I read nutrition labels like I understand them. I don't. I just nod thoughtfully and put things back like I'm some kind of wellness expert.

"Hmm, seventeen grams of... things. That seems like too many things."

"It has three different settings! And look at this attachment! This little brush thing goes in corners!"

My friend just stared at me like I'd been replaced by a suburban mom from 1987.

shrugs confidently

Because being an adult isn't about having it all figured out. It's about confidently pretending you know what you're doing while secretly googling "how to fold a fitted sheet" for the hundredth time.

And if that's not the American dream, I don't know what is.

pause

Also, if anyone actually knows how to fold a fitted sheet, please find me after the show. I'll pay you.

mic drop gesture

Thank you, you've been a wonderful audience! Don't forget to tip your servers and call your parents – they're worried about you!

Total time: approximately 3 minutes when delivered at normal comedy pace

Gemini 2.5 Flash Preview vs Claude Sonnet 4

Which is better, Gemini 2.5 Flash Preview or Claude Sonnet 4?

Key Differences Between Gemini 2.5 Flash Preview and Claude Sonnet 4

Why Gemini 2.5 Flash Preview?

Why Claude Sonnet 4?

Favorites

Logic Puzzlereasoning

Gemini 2.5 Flash Preview

Claude Sonnet 4

Math Misconception Testreasoning

Gemini 2.5 Flash Preview

Claude Sonnet 4

Stochastic Consistency Testanalysis

Gemini 2.5 Flash Preview

Claude Sonnet 4

SVG Layout Challengeimage generation

Gemini 2.5 Flash Preview

Claude Sonnet 4

Xbox Controller SVG Artimage generation

Gemini 2.5 Flash Preview

Claude Sonnet 4

Generate a Stand-Up Routineconversation

Gemini 2.5 Flash Preview

Claude Sonnet 4

"Adulting is Hard"

Linear App Cloneweb design

Gemini 2.5 Flash Preview

Claude Sonnet 4

Interactive Catan Boardweb design

Gemini 2.5 Flash Preview

Claude Sonnet 4

World Map SVGimage generation

Gemini 2.5 Flash Preview

Claude Sonnet 4

Random Tailwind Webappweb design

Gemini 2.5 Flash Preview

Claude Sonnet 4

Surprise Animal SVGimage generation

Gemini 2.5 Flash Preview

Claude Sonnet 4

Simple 7-Ingredient Recipeconversation

Gemini 2.5 Flash Preview

Claude Sonnet 4

This matchup has more rounds

Style Comparison

Common questions

What is the difference between Gemini 2.5 Flash Preview and Claude Sonnet 4?

Which is better, Gemini 2.5 Flash Preview or Claude Sonnet 4?

How much does Gemini 2.5 Flash Preview cost compared to Claude Sonnet 4?

How are Gemini 2.5 Flash Preview vs Claude Sonnet 4 votes collected on Rival?

Why Gemini 2.5 Flash Preview?

Why Claude Sonnet 4?

Favorites

Logic Puzzlereasoning

Gemini 2.5 Flash Preview

Claude Sonnet 4

Math Misconception Testreasoning

Gemini 2.5 Flash Preview

Claude Sonnet 4

Stochastic Consistency Testanalysis

Gemini 2.5 Flash Preview

Claude Sonnet 4

SVG Layout Challengeimage generation

Gemini 2.5 Flash Preview

Claude Sonnet 4

Xbox Controller SVG Artimage generation

Gemini 2.5 Flash Preview

Claude Sonnet 4

Generate a Stand-Up Routineconversation

Gemini 2.5 Flash Preview

Claude Sonnet 4

"Adulting is Hard"

Linear App Cloneweb design

Gemini 2.5 Flash Preview

Claude Sonnet 4

Interactive Catan Boardweb design

Gemini 2.5 Flash Preview

Claude Sonnet 4

World Map SVGimage generation

Gemini 2.5 Flash Preview