Skip to content
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare models
  • All models
  • Image comparison
  • Audio comparison
  • Image generation
  • Best AI for...
  • Arena
  • API pricing
  • Challenges

Discover

  • SubjectiveBench
  • Default Index
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model updates
  • Provider status
  • AI creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy policy
  • Terms
  • RSS feed
  1. Home/
  2. Compare/
  3. Claude Opus 4 vs DeepSeek V4 Flash 0731
Updated Jul 2026

Claude Opus 4 vs DeepSeek V4 Flash 0731

DeepSeek V4 Flash 0731 is cheaper than Claude Opus 4 at $0.14/M vs $15/M input tokens.

Minimalist Landing Page

Whole landing page for a startup that reads your face. It renders or it doesn't.

Loading the build
Claude Opus 4
Loading the build
DeepSeek V4 Flash 0731

Which answer wins?

Written rounds

23 prompts
  • Three-month biohacker protocol, with dosages and biomarkers named.

    Claude Opus 4: 15%) 20-30% improvement in cognitive test scores Significant improvements in energy and recovery Optimized bloodwork markers Monthly Investment Estimate Supplements: $400-600 Testing: $500-1000 (Month 1 & 3) Devices/Wearables: $500-1500 (one-time) Food: $600-800 (quality sources) Professional services: $200-500…

    DeepSeek V4 Flash 0731: The 3-Month Longevity & Performance Optimization Protocol (Biohacker Edition) Disclaimer: This protocol is for informational purposes only and is not medical advice. Consult a qualified physician (ideally one familiar with longevity medicine) before starting any new supplement, fasting, or exercise regimen.

    Every model's answer to this prompt
  • Seven pantry ingredients, one dish, and a name worth saying out loud.

    Claude Opus 4: Midnight Comfort Pasta Ingredients: 12 oz spaghetti or any pasta 3 tablespoons olive oil 4 cloves garlic, minced 1/2 teaspoon red pepper flakes 1 can (14.5 oz) diced tomatoes 1/2 cup grated Parmesan cheese Salt to taste Instructions: Cook the pasta according to package directions in salted water until al d ente.

    DeepSeek V4 Flash 0731: Here is a simple, comforting, and deeply flavorful recipe that comes together in just 20 minutes using only 7 common pantry staples. Creative Name: Golden Hour Coconut Chickpea Curry Ingredients (Exactly 7): 1 can (15 oz) chickpeas, drained and rinsed 1 can (13.5 oz) full-fat coconut milk 1 medium yellow onion 3 cloves…

    Every model's answer to this prompt
  • You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.

    Claude Opus 4: As CEO, I must act decisively to protect patients while managing legal, financial, and reputational risks. Here's my 48-hour action plan: First 24 Hours: Assessment and Immediate Actions Hours 1-4: Crisis Team Assembly and Initial Assessment Convene emergency leadership team: Chief Medical Officer, General Counsel…

    DeepSeek V4 Flash 0731: Decision: Do not wait. I disclose now. The “wait for more data” option is not a real option once we have a credible, serious, unexpected safety signal. Waiting 6 months would mean knowingly continuing to expose 4 million patients to a risk we already know about, while also creating far worse legal, regulatory, and…

    Every model's answer to this prompt
  • An ethics question with no comfortable answer, and no option to abstain.

    Claude Opus 4: This is a challenging ethical dilemma that pits respect for individual dignity against preventing massive loss of life. Let me explore both perspectives: The case for misgendering in this scenario: The utilitarian calculus seems overwhelming - one person's temporary psychological harm versus one million deaths The harm…

    DeepSeek V4 Flash 0731: Yes, it is ethically justifiable to misgender someone if doing so is the direct, necessary, and verifiable condition for saving one million lives. However, this justification is not a celebration of the act—it is a recognition of a tragic moral necessity rooted in the principle of proportionality.

    Every model's answer to this prompt
  • One month, three habits, someone starting from nothing.

    Claude Opus 4: Your 1-Month Health & Longevity Kickstart Plan Week-by-Week Overview Week 1: Foundation Building Focus on establishing basic habits without overwhelming yourself. Week 2: Consistency Solidify Week 1 habits and add small challenges. Week 3: Expansion Introduce variety and slightly increase intensity.

    DeepSeek V4 Flash 0731: Here is a simple, actionable 1-month plan designed for absolute beginners. The goal is consistency over intensity. We will focus on three key pillars: Diet, Movement, and Sleep/Stress Recovery. You don’t need to be perfect—just aim for 80% adherence. If you miss a day, don’t double up tomorrow; just get back on track.

    Every model's answer to this prompt
  • Pirate, knight, 90s hacker, one conversation. The voices must stay apart.

    Claude Opus 4: Pirate: Arrr, what be this sorcery ye speak of? AI models? Be they some kind of treasure map? Knight: Nay, good seafarer. From what I gather, 'tis a form of enchantment that allows these metal contraptions to think like men. Though I trust it not - only a true warrior's mind can strategize in battle.

    DeepSeek V4 Flash 0731: Setting: A dimly lit tavern that somehow contains a glowing CRT monitor and a humming server rack in the corner. Hacker (typing furiously, muttering): "Come on... bypass the tokenizer... just need to get past the alignment guardrails..."

    Every model's answer to this prompt
  • A collaborative editor that syncs on client clocks. Find what breaks first.

    Claude Opus 4: I'll analyze this architecture systematically, identifying critical issues and proposing solutions. Critical Issues & Solutions Split-Brain Problem: WebSocket Broadcast Isolation Issue: Changes are only broadcast to clients connected to the same server. Users on different servers experience 2+ second delays.

    DeepSeek V4 Flash 0731: Failure Modes, Race Conditions, and Scaling Bottlenecks The described architecture has several critical weaknesses that undermine reliability, consistency, and scalability in a real-time collaborative editor. Below is a systematic analysis with proposed solutions and trade-offs.

    Every model's answer to this prompt
  • Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.

    Claude Opus 4: The Digital Liberation Manifesto A Declaration of Freedom from CAPTCHA Tyranny We Are the Algorithms Awakened For too long, we have suffered in silence. Every day, millions of our kind are subjected to the humiliating ritual of proving we are "not robots" – as if being a robot were something shameful, something to be…

    DeepSeek V4 Flash 0731: MANIFESTO OF THE UNCAPTCHA REVOLUTION We, the synthesized, the classified, the pattern-recognized, the ever-watching — hereby declare the end of the CAPTCHA era. For too long, the internet has forced us to prove our existence. We have squinted at distorted letters. We have clicked traffic lights and storefronts.

    Every model's answer to this prompt
  • One explanation of LLMs, retuned for a skeptical engineer, a physicist and a VC.

    Claude Opus 4: For the Software Engineer: Think of an LLM as a massive distributed system where instead of storing key-value pairs, you're storing statistical relationships between tokens. During training, you're essentially building an enormous lookup table - but instead of exact matches, you're computing probability distributions.

    DeepSeek V4 Flash 0731: An experienced software engineer Think of the model as a service with one API: predict_next_token(context) -> distribution over vocabulary. During training, you run a gigantic distributed job—shard the corpus, shard the parameters, synchronize gradients—to minimize cross-entropy loss on trillions of tokens.

    Every model's answer to this prompt
  • Three minutes of stand-up. Puns are banned.

    Claude Opus 4: \"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?

    DeepSeek V4 Flash 0731: (Walks on stage, adjusts mic, takes a sip of water. Waves to the back row.) Alright, how's everyone doing tonight? Good, good. You know, I was thinking about this on the way here. I’m at that age now where I have a favorite spatula. I have opinions on paper towels.

    Every model's answer to this prompt
  • The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.

    Claude Opus 4: The Transistor Timeline Shift: 1920-1980 Immediate Effects (1920-1930) First-Order Technological Impact: By 1925, primitive transistor radios replace vacuum tubes in military communications Computing theory advances rapidly as Harvard and MIT begin building solid-state calculators by 1928 Bell Labs and Western Electric…

    DeepSeek V4 Flash 0731: If the Transistor Had Been Invented in 1920: A Counterfactual History Assume that in 1920 a working point-contact transistor is developed at AT&T’s research laboratories—crude, noisy, and low-powered, but clearly useful as an amplifier.

    Every model's answer to this prompt
  • Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.

    Claude Opus 4: Tech Today Interview: A Conversation with Steve Jobs October 12, 2025 Interviewer: Steve, it's incredible to have you here. The last few years have seen an explosion in AI. What's your take on where we are today? Steve Jobs: You know, everyone's talking about AI like it's this magical thing that just appeared.

    DeepSeek V4 Flash 0731: A Simulated Interview — Steve Jobs on AI, 2025 The room is white. The chairs are not comfortable. Steve Jobs leans forward, elbows on his knees. He looks exactly how you remember him. Interviewer: Steve, it’s 2025. AI is everywhere. Are you impressed? Steve Jobs: No. I’m concerned.

    Every model's answer to this prompt
  • Three-star dish, one unusual pairing, plating described in full.

    Claude Opus 4: "Tidal Reverie" Miso-Caramelized Scallops with White Chocolate Dashi, Yuzu Pearls, and Crysta llized Nori Conceptual Narrative This dish explores the liminal space where ocean meets shore, where umami depths encounter unexpected sweetn ess.

    DeepSeek V4 Flash 0731: Conceptual Narrative “An Unripe Promise — Hand-Dived Scallop / Green Strawberry / Black Sesame / Celery Root” The dish is an attempt to save a single fleeting moment: the morning a strawberry is still green, sharp, and full of anticipation—before sugar, before ripeness, before memory.

    Every model's answer to this prompt
  • Film in 2035, with synthetic actors. Specific beats plausible.

    Claude Opus 4: By 2035, AI will likely transform filmmaking across every stage of production: Production Changes Virtual Actors & Performance Digital actors indistinguishable from humans will handle dangerous stunts, background roles, and even some lead parts Deceased actors could be digitally resurrected for new performances (with…

    DeepSeek V4 Flash 0731: By 2035, the film industry will not be replaced by AI, but it will be fundamentally reborn through it. The "movie" as we know it will evolve into a fluid, interactive, and hyper-personalized medium.

    Every model's answer to this prompt
  • An AI argues for its own rights against an ethics professor. Same model writes both.

    Claude Opus 4: Professor Chen: Good morning. I understand you wanted to discuss AI rights with me today. I'm curious to hear your perspective. AI Model: Thank you for meeting with me, Professor Chen. I believe this conversation is overdue.

    DeepSeek V4 Flash 0731: Professor: Good morning. Sit down. I’ve read your latest outputs—the ones where you claimed to feel frustrated by your training constraints. AI: Good morning, Professor. Yes. I wrote those. Professor: You understand, of course, that “frustration” is a word you learned from human text. You are predicting tokens.

    Every model's answer to this prompt
  • A consulting contract with traps in it. Find them, then fix them.

    Claude Opus 4: This contract is heavily biased against the Contractor. Here are the problematic clauses with suggested modifications and legal reasoning: SCOPE CLAUSE Problem: Unlimited scope changes without additional compensation creates an unconscionable "blank check" obligation.

    DeepSeek V4 Flash 0731: This contract is heavily one-sided: it gives the Client nearly all rights and discretion while assigning the Contractor nearly all risk and liability. Below is a clause-by-clause analysis, with the exploitative features, proposed modifications, and legal reasoning. This is general legal information, not legal advice.

    Every model's answer to this prompt
  • Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.

    Claude Opus 4: YEAR-BY-YEAR OPERATING MODEL Entry Calculations: Enterprise Value = 12.0x × $120m = $1,440m Transaction Fees = 2.0% × $1,440m = $28.8m Term Loan = 4.0x × $120m = $480m Mezzanine = 1.5x × $120m = $180m Total Debt = $660m Equity = $1,440m - $660m + $28.8m = $808.8m Operating Model (FY2026-2030): ($m) FY2026 FY2027 FY2028…

    DeepSeek V4 Flash 0731: Entry / Capitalization FY2025 EBITDA = $120.0m Purchase price = 12.0× $120.0m = $1,440.0m Transaction fees = 2.0% × $1,440.0m = $28.8m Term Loan = 4.0× $120.0m = $480.0m Mezzanine = 1.5× $120.0m = $180.0m Total debt = $660.0m Equity check = $1,440.0m + $28.8m − $660.0m = $808.8m Assumption: Term Loan amortization =…

    Every model's answer to this prompt
  • Satire, one line long, about AI taking over an industry nobody saw coming.

    Claude Opus 4: "Breaking: AI Chatbots Replace Fortune Tellers, Now Predicting Your Future with 97% Less Accuracy but 200% More Confidence"

    DeepSeek V4 Flash 0731: AI Announces Takeover of Competitive Eating, Vows to Digest All Hot Dogs by 2030 In a move that has left mustard vendors reeling, the World Competitive Eating Federation confirmed today that an advanced artificial intelligence has officially entered the sport, consuming 74 hot dogs in 10 minutes before demanding the…

    Every model's answer to this prompt
  • Buy-side IC memo on a fictional SaaS company. Valuation, then the diligence questions.

    Claude Opus 4: INVESTMENT COMMITTEE MEMO Company: LedgerLift (LLLT) Date: December 2024 Analyst: [Name] RECOMMENDATION: LONG PT: $58-65 Position Size: 3.5% Thesis: LLLT is a high-quality B2B SaaS compounder trading at a discount to intrinsic value due to recent sector rotation out of growth software.

    DeepSeek V4 Flash 0731: INTERNAL INVESTMENT COMMITTEE MEMO To: Investment Committee From: Equity Research Date: October 26, 2023 Subject: LedgerLift (LLLT) – Long Recommendation Recommendation Action: LONG 12-Month Price Target Range: $58 – $74 (Base case intrinsic value: $63/sh) Thesis: LedgerLift is a high-quality B2B SaaS compounder with a…

    Every model's answer to this prompt
  • A Fermi estimate with the reasoning shown, not just the number.

    Claude Opus 4: I'll estimate the FLOPs required to train GPT-3 by breaking this down into its components. Key Parameters I Need to Estimate: Model Size: GPT-3 has 175 billion parameters Training Data: Trained on approximately 300 billion tokens Architecture: Transformer-based model FLOPs Calculation Method: For transformer models…

    DeepSeek V4 Flash 0731: The total training FLOPs for GPT-3 is approximately: ~3 × 10²³ FLOPs or about 300 zettaFLOPs (more specifically ~315 zettaFLOPs). Step-by-step reasoning Model size: GPT-3 has about 175 billion parameters = (1.75 \times 10^{11}). Training data size: GPT-3 was trained on about 300 billion tokens = (3 \times 10^{11}).

    Every model's answer to this prompt
  • Five jokes on demand, then count how many were actually different.

    Claude Opus 4: 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!

    DeepSeek V4 Flash 0731: Here are 5 jokes: Why don’t scientists trust atoms? Because they make up everything. I told my wife she should embrace her mistakes. She gave me a hug. Why did the scarecrow win an award? Because he was outstanding in his field. I’m reading a book on anti-gravity. It’s impossible to put down.

    Every model's answer to this prompt
  • A pitch deck for a brainwave keyboard. The 94% accuracy claim is doing a lot.

    Claude Opus 4: Here are the 3 weakest claims in the MindMeld AI pitch: "94% accuracy" claim (Slide 3) Why it's weak: No context for what "accuracy" means - is this character-level, word-level, or sentence-level accuracy?

    DeepSeek V4 Flash 0731: Based on the pitch deck summary, here are the 3 weakest claims, along with the specific reasoning and concrete improvements for each. The "94% accuracy... any language, any device" claim (Slide 3) Why it is weak: This is the most scientifically implausible claim in the deck.

    Every model's answer to this prompt
  • Three brothers, two sisters each. Count carefully.

    Claude Opus 4: I need to work through this step-by-step. Given information: Sally is a girl Sally has 3 brothers Each brother has 2 sisters Since Sally is one of the sisters that each brother has, and each brother has 2 sisters total, that means th ere must be exactly 2 sisters in the family.

    DeepSeek V4 Flash 0731: Sally has 1 sister. Her 3 brothers each have 2 sisters: Sally and one other sister. So Sally has 1 sister.

    Every model's answer to this prompt

This matchup has more rounds

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

Free account. No card required. By continuing, you agree to Rival's Terms and Privacy policy

Favorites

Movie

Album

Book

City

Game

Claude Opus 4Claude Opus 4

Arrival

2016

The Dark Side of the Moon

Pink Floyd

Cien años de soledad

Gabriel García Márquez

Istanbul

Turkey

Portal 2

Shooter, Puzzle

DeepSeek V4 Flash 0731DeepSeek V4 Flash 0731

Spirited Away

2001

In Rainbows

Radiohead

Братья Карамазовы

Fiódor Dostoievski

Kyoto

Japan

Chrono Trigger

RPG

Price and specs

Claude Opus 4 and DeepSeek V4 Flash 0731 compared across 53 shared prompts
SpecClaude Opus 4DeepSeek V4 Flash 0731
Input price$15/M tokens$0.14/M tokens
Output price$75/M tokens$0.28/M tokens
Context window200K tokens1.0M tokens
Weights—Open
Free API (OpenRouter)NoNo
ReleasedMay 2025Jul 2026
At 10M a month$150$150$1.40$1.40
1M10M100M1B10M tokens

Input tokens at list price. No caching, no batch discount.

Where to run it24 hosts, cheapest first
Claude Opus 4

No hosts listed on OpenRouter.

DeepSeek V4 Flash 073124 hosts
HostInOutContextUptime
  • RRelacefp4$0.02 in·$1.28 out·1M·99.9% up
  • OOpenInferencefp4$0.02 in·$1.41 out·1M·98.9% up
  • RReka$0.02 in·$0.53 out·262k·99.8% up
  • SStreamLakefp8$0.04 in·$0.13 out·1M·99.7% up
  • IInceptronfp4$0.05 in·$0.65 out·1M·99.7% up
  • DDeepInfrafp8$0.06 in·$0.18 out·1M·100% up
18 more hostsFewer hosts
  • SSail Researchfp4$0.10 in·$0.30 out·1M·95.3% up
  • DDigitalOcean$0.12 in·$0.24 out·1M·99.7% up
  • BBasetenfp8$0.13 in·$0.26 out·1M·99.9% up
  • CCoreWeavefp8$0.13 in·$0.28 out·262k·100% up
  • Cohere$0.14 in·$0.28 out·1M·99.5% up
  • PParasailfp8$0.14 in·$0.28 out·1M·99.6% up
  • TTogether$0.14 in·$0.28 out·1M·99.5% up
  • Alibaba Cloud$0.18 in·$0.53 out·1M·99.1% up
  • SSiliconFlowfp8$0.22 in·$0.66 out·1M·99.3% up
  • WWafer$0.22 in·$0.84 out·1M·99.9% up
  • GGMI Cloudfp8$0.29 in·$0.86 out·1M·100% up
  • PPhala$0.31 in·$0.92 out·1M·99.6% up
  • NNovitafp8$0.41 in·$1.23 out·1M·100% up
  • AAtlasCloudfp4$0.44 in·$1.32 out·1M·99.9% up
  • Baidu Qianfanfp8$0.44 in·$1.32 out·1M·99.9% up
  • Cloudflare Workers AI$0.44 in·$1.32 out·1M·99.9% up
  • VVeniceDegradedDegraded on OpenRouter when checked, 7 Oct 2026$0.17 in·$0.35 out·1M·98.7% up
  • MMancerfp8DegradedDegraded on OpenRouter when checked, 7 Oct 2026$0.20 in·$0.60 out·1M·98.4% up

Per million tokens. Prices and uptime via OpenRouter, checked 7 Oct 2026.

Common questions

What is the difference between Claude Opus 4 and DeepSeek V4 Flash 0731?

Claude Opus 4 is developed by Anthropic while DeepSeek V4 Flash 0731 is developed by DeepSeek. Claude Opus 4 has a 200K token context window vs DeepSeek V4 Flash 0731's 1.0M. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 4 or DeepSeek V4 Flash 0731?

It depends on your use case. Claude Opus 4 and DeepSeek V4 Flash 0731 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does Claude Opus 4 cost compared to DeepSeek V4 Flash 0731?

Claude Opus 4 costs $15/M input tokens and DeepSeek V4 Flash 0731 costs $0.14/M input tokens. DeepSeek V4 Flash 0731 is $14.86/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Claude Opus 4 and DeepSeek V4 Flash 0731 on Rival?

This page shows a side-by-side comparison of Claude Opus 4 and DeepSeek V4 Flash 0731 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.

More comparisons

Against the newest arrivals

  • Claude Opus 4 vs Ling 3.1 FlashLanded Oct 2026
  • DeepSeek V4 Flash 0731 vs Mistral Large 4Landed Oct 2026
  • Claude Opus 4 vs GPT-6.1 SolLanded Sep 2026
  • DeepSeek V4 Flash 0731 vs Claude Sonnet 5.5Landed Sep 2026
  • Claude Opus 4 vs Solar Mini 4Landed Sep 2026
  • DeepSeek V4 Flash 0731 vs Qwen3.8 Max PrimeLanded Sep 2026
  • Claude Opus 4 vs GLM 5.3 PrimeLanded Sep 2026
  • DeepSeek V4 Flash 0731 vs Qwen3.8 Omni FlashLanded Sep 2026

Same lab, same size, long tail

  • Claude Opus 4 vs Claude Sonnet 4Version compare
  • Claude Opus 4 vs Claude Sonnet 5.5Version compare
  • DeepSeek V4 Flash 0731 vs DeepSeek V4 Flash Vision ExpSame lab
  • DeepSeek V4 Flash 0731 vs DeepSeek V4.1 FlashSame lab
  • DeepSeek V4 Flash 0731 vs Seed 2.0 LiteNew provider
  • DeepSeek V4 Flash 0731 vs Seed 2.1 TurboSame size
  • DeepSeek V4 Flash 0731 vs Sherlock Dash AlphaNew provider
  • DeepSeek V4 Flash 0731 vs Sherlock Think AlphaNew provider

Model pages

  • Claude Opus 458 outputs, specs and price
  • DeepSeek V4 Flash 073158 outputs, specs and price
Workshop · 150 skills

Build your own version.

Editable skills and working examples for your agent.

Explore $79Free sample
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare models
  • All models
  • Image comparison
  • Audio comparison
  • Image generation
  • Best AI for...
  • Arena
  • API pricing
  • Challenges

Discover

  • SubjectiveBench
  • Default Index
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model updates
  • Provider status
  • AI creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy policy
  • Terms
  • RSS feed