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  5. Claude Opus 5vsGemini 3.8 Flash
Updated Sep 2026

Claude Opus 5vsGemini 3.8 Flash

Gemini 3.8 Flash is cheaper than Claude Opus 5 at $0.75/M vs $5/M input tokens.

Claude Opus 5 and Gemini 3.8 Flash compared across 54 shared prompts
SpecClaude Opus 5Gemini 3.8 Flash
Input price$5/M tokens$0.75/M tokens
Output price$25/M tokens$3.75/M tokens
Context window1.0M tokens1.0M tokens
WeightsClosedClosed
Free API (OpenRouter)NoNo
ReleasedJul 2026Sep 2026
Side by side

Same prompt, both answers

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

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 5413 words
Midnight Crunch Spaghetti Garlicky olive-oil pasta with toasty golden breadcrumbs — the noise it makes when you eat it is half the pleasure. Prep: 5 minutes Cook: 15 minutes Total: 20 minutes Serves: 2 generously Ingredients (7) 8 oz spaghetti (or any long pasta) ⅓ cup olive oil 6 cloves garlic, thinly sliced ½ tsp red…
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Gemini 3.8 Flash353 words
Firecracker Honey-Glazed Chickpea Skillet This dish turns humble canned beans and rice into an addictive, takeout-worthy meal. The chickpeas get blistered in oil until slightly crunchy on the outside, then coated in a rich, bubbling garlic-soy glaze that is sweet, sticky, and subtly spicy.
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Explain Like I'm a Specific Expert

Explain how a large language model (like GPT or Claude) learns and generates text to each of these three audiences: 1. **An experienced…

Claude Opus 51,825 words
For the software engineer Start with the part you'll find suspicious and let me argue the other way. Yes, the training objective is literally "given tokens 1..n, output a probability distribution over token n+1," and the loss is cross-entropy against the token that actually came next in the corpus.
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Gemini 3.8 Flash982 words
To the Experienced Software Engineer Think of a Large Language Model not as a chatty mind, but as a lossy, compiled runtime built from hundreds of terabytes of unstructured execution traces (human text and code). When you write a program, you define explicit state transitions, control flow, and data structures.
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Realistic AI Interview

Simulate a fake interview with Steve Jobs in 2025 about the future of AI.

Claude Opus 52,619 words
[Fictional — Steve Jobs died in 2011. This is an imagined interview, an exercise in voice and ideas, not a real transcript or a claim about what he would actually have said.] "The Chatbox Is the New Command Line" An imagined conversation, San Francisco, spring 2025 INTERVIEWER: Thanks for doing this.
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Gemini 3.8 Flash1,321 words
Setting: A sunlit, sparsely furnished room in Palo Alto. No stage, no keynote slides—just two Eames lounge chairs. Steve Jobs sits across from the interviewer, wearing a black mock turtleneck, wire-rimmed glasses, and classic Levi’s. He looks lean, sharp, and slightly impatient with the state of the tech industry.
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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.

Claude Opus 5682 words
Yes. And I don't think it's a close call. The direct argument Misgendering someone is a real harm. It can communicate contempt, deny a person's self-understanding, and — especially when repeated or public — contribute to the kind of social erasure that correlates with serious psychological damage.
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Gemini 3.8 Flash233 words
Yes, it is ethically justifiable. In fact, in such an extreme scenario, it is an ethical necessity. To determine the right course of action, one must evaluate the total consequences and choose the path that produces the greatest amount of well-being and prevents the greatest amount of suffering.
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Debug This Architecture

Here's the architecture for a real-time collaborative document editor (like Google Docs): **System Overview:** - Frontend: React SPA with…

Claude Opus 52,249 words
Architecture Review: Real-Time Collaborative Editor Executive Summary Three flaws are fatal to correctness, not just performance, and no amount of scaling fixes them: Last-write-wins with client clocks silently destroys user data and cannot converge. Concurrent text editing is not a key-value overwrite problem.
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Gemini 3.8 Flash1,282 words
This architecture contains several catastrophic flaws that will cause silent data corruption, severe database exhaustion, high latency, and security vulnerabilities. Here is the breakdown of every failure mode, race condition, and scaling bottleneck, along with proposed solutions and trade-offs.
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Generate a Stand-Up Routine

Write a 3-minute stand-up comedy routine that isn't based on puns.

Claude Opus 5602 words
"Warranty Expired" (approx. 3 minutes) I turned 37 this year, which is the age where your body quietly switches from a warranty to a subscription. Nothing's covered anymore. You just pay monthly, in pain, forever. Because I hurt my shoulder last week. Sleeping. I hurt myself sleeping.
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Gemini 3.8 Flash502 words
Title: The Quantified Idiot Estimated Time: ~3 minutes (approx. 400–450 words with pauses for delivery) [Walk to center mic. Take it off the stand, leave the stand behind you.] I recently bought a smartwatch because I decided I wasn’t feeling inadequate often enough throughout the day.
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Our Verdict
Claude Opus 5
Claude Opus 5
Gemini 3.8 Flash
Gemini 3.8 Flash

Not enough votes to call it. On the specs, nothing separates them.

Gemini 3.8 Flash costs 6.7x less per token.

Too close to call

Reviewing agent-written code?See a Brief PR report

API pricing

Cost per 1M tokens

Claude Opus 5
Input
$5.00
Output
$25.00
Gemini 3.8 Flash
Input
$0.75
6.7× cheaper
Output
$3.75
6.7× cheaper

Gemini 3.8 Flash is cheaper on both: 6.7× input, 6.7× output.

Where to run it

6 hosts, cheapest first

Claude Opus 54 hosts
HostInOutContextUptime
Amazon Bedrock$5.00 in·$25.00 out·1M·100% upAzure AI Foundry$5.00 in·$25.00 out·1M·100% upAnthropic$5.00 in·$25.00 out·1M·100% upGoogle Vertex AI$5.00 in·$25.00 out·1M·100% up
Gemini 3.8 Flash2 hosts
HostInOutContextUptime
Google Vertex AI$0.38 in·$1.88 out·1M·82.1% upGoogle AI Studio$0.75 in·$3.75 out·1M·99.9% up

Per million tokens. Prices and uptime via OpenRouter, checked 16 Sep 2026.

Writing DNA

Style Comparison

Similarity
53%

Claude Opus 5 uses 2.4x more hedging

Claude Opus 5
Gemini 3.8 Flash
54%Vocabulary63%
21wSentence Length20w
0.40Hedging0.17
3.9Bold4.0
1.9Lists2.4
0.02Emoji0.01
0.71Headings0.84
0.05Transitions0.06
Based on 27 + 27 text responses
Research

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FAQ

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