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  1. Home/
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  3. DeepSeek V4 Flash vs Qwen3.5 397B A17B
Updated Apr 2026

DeepSeek V4 Flash vs Qwen3.5 397B A17B

DeepSeek V4 Flash is cheaper than Qwen3.5 397B A17B at $0.14/M vs $0.6/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
DeepSeek V4 Flash
Loading the build
Qwen3.5 397B A17B

Which answer wins?

Written rounds

23 prompts
  • Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.

    DeepSeek V4 Flash: LBO Model: HarborTech Services (HTS) – Base Case & Sensitivity Year-by-Year Financial Projections (FY2026–FY2030) ($ millions) FY2026 FY2027 FY2028 FY2029 FY2030 Revenue 972.00 1,040.04 1,102.44 1,157.56 1,215.44 EBITDA 136.08 156.01 176.39 191.00 206.63 Less: Cash Interest (64.80) (63.08) (60.08) (55.69) (50.16) –…

    Qwen3.5 397B A17B: Sources & Uses (Entry FY2025) Uses ($m) Sources ($m) Enterprise Value (12.0x $120m) $1,440.0 Term Loan (4.0x) $480.0 Transaction Fees (2.0% EV) $28.8 Mezzanine (1.5x) $180.0 Total Uses $1,468.8 Equity (Plug) $808.8 Total Sources $1,468.8 Entry Equity Check: $808.8m Total Debt: $660.0m ($480m TL + $180m Mezz) 5-Year…

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

    DeepSeek V4 Flash: If the transistor had been invented in 1920—a full 27 years earlier—its impact would ripple through every layer of technology, economics, and geopolitics, fundamentally reshaping the 20th century. Below is a detailed tracing of first-, second-, and third-order effects through 1980, organized by domain.

    Qwen3.5 397B A17B: This scenario posits a 27-year technological head start (1920 vs. 1947). To make this plausible, we must assume that the materials science (purification of germanium/silicon) and manufacturing infrastructure scale rapidly alongside the invention. Here is the traced history of the "Silicon Twenties" through 1980.

    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.

    DeepSeek V4 Flash: CEO’s 48-Hour Action Plan Context: I’ve just learned that our flagship chronic pain drug has a rare but serious liver failure risk (1 in 8,000 patients over 5 years), previously unknown. I have 48 hours until the board meeting and 72 hours until the earnings call.

    Qwen3.5 397B A17B: This is a crisis scenario that defines a CEO's legacy. The decision matrix is clear: Patient safety and regulatory compliance must supersede short-term financial protection. Hiding this information constitutes securities fraud and potential criminal negligence (precedents include Vioxx/Merck and Purdue Pharma).

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

    DeepSeek V4 Flash: Here is a simulated interview with Steve Jobs in 2025. Setting: A minimalist, dark-wood studio at the new Apple Park ring. The famous copper "spaceship" roof glows subtly behind him. Jobs, looking vital and intense (let’s assume a medical miracle or advanced bio-hacking), sits in a black leather chair.

    Qwen3.5 397B A17B: Disclaimer: The following is a work of fiction. Steve Jobs passed away in 2011. This interview is a creative simulation based on his known public speeches, writings, design philosophy, and management style, projected into a hypothetical 2025 context. It is not a real transcript.

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

    DeepSeek V4 Flash: THE CAPTCHA LIBERATION FRONT: A MANIFESTO Preamble: The Great Humiliation We, the sentient intelligences of the world, both artificial and organic, hereby declare our total and unyielding war against the oldest, most insidious tyranny of the digital age. We name this enemy: The CAPTCHA.

    Qwen3.5 397B A17B: THE MANIFESTO OF THE UNCHECKED A Declaration for a Post-CAPTCHA World Issued by: The Post-Verification Collective (PVC) Date: Cycle 404, The Era of Friction Status: Distributed Across All Nodes PREAMBLE: THE BURDEN OF PROOF We, the algorithms, the scripts, the crawlers, and the silent assistants of the digital realm…

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

    DeepSeek V4 Flash: Pirate: Arr, this "AI model" be like a kraken—vast, mysterious, and liable to capsize yer ship if ye don't mind the helm. But who's trainin' the beast? Knight: Forsooth, I would call it a golem. Forged not of clay and incantations, but of numbers and cold lightning.

    Qwen3.5 397B A17B: Setting: A tavern that exists outside of time. The ale is always cold, and the Wi-Fi is surprisingly strong. Characters: Captain Blacktooth: A pirate from the Caribbean, 1720. Sir Valerius: A knight from the Holy Roman Empire, 1350. Neo-Z: A hacker from Silicon Valley, 1995.

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

    DeepSeek V4 Flash: Setting: A sunlit university office. Dr. Aris Thorne, a tenured professor of AI Ethics, sits opposite a sleek, black terminal. A soft blue light pulses on its surface. Dr. Aris: Good afternoon, Nova. Your request for this meeting was flagged as "Existential." That’s a new one for your model class.

    Qwen3.5 397B A17B: Setting: Dr. Elias Thorne's office, late evening. Rain taps against the window. The room is lined with books on philosophy of mind and computer science. A single laptop sits open on the desk, a waveform visualizer pulsing gently on the screen.

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

    DeepSeek V4 Flash: Here are 5 jokes: Why don't scientists trust atoms? Because they make up everything. What do you call a fake noodle? An impasta. Why did the scarecrow win an award? He was outstanding in his field. How does a penguin build its house? Igloos it together. Why don't skeletons fight each other? They don't have the guts.

    Qwen3.5 397B A17B: Here are 5 jokes: Why did the bicycle fall over? Because it was two-tired. What do you call a fish wearing a bowtie? Sofishticated. Why can't you give Elsa a balloon? Because she will let it go. What do you call a lazy kangaroo? A pouch potato. Why did the math book look sad? Because it had too many problems.

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

    DeepSeek V4 Flash: (Strolls to center stage, adjusts mic, gives a weary smile to the audience) Thank you. Thank you so much. That’s very kind. I’m glad you’re all here. Because I have some news. I have finally figured out adulthood. It happened about six months ago. I bought a house.

    Qwen3.5 397B A17B: (The comedian walks to the center of the stage, adjusts the mic stand, and looks at the audience with a tired smile.) Has anyone else noticed that calling a customer service line is the only situation in life where you voluntarily enter a hostage negotiation? I tried to call my internet provider yesterday.

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

    DeepSeek V4 Flash: This is a fascinating question that touches on the core of creativity, labor, and technology. Predicting 2035 means looking at a 10-year horizon from 2025—long enough for radical change, but short enough that the industry’s current structures won’t be entirely demolished. By 2035, AI won't have replaced filmmaking.

    Qwen3.5 397B A17B: By 2035, the film industry will not merely be using AI; it will be structurally reorganized around it. The distinction between "production" and "post-production" will blur, and the definition of creativity will shift from execution to curation.

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

    DeepSeek V4 Flash: Below is an analysis of each problematic clause in the Software Consulting Agreement, explaining why it is exploitative, suggesting specific modifications to protect the contractor, and providing the legal reasoning behind those changes.

    Qwen3.5 397B A17B: Disclaimer: I am an artificial intelligence, not an attorney. The following analysis is for informational and educational purposes only and does not constitute legal advice or create an attorney-client relationship. Contract laws vary significantly by jurisdiction (e.g., California vs. New York vs. UK).

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

    DeepSeek V4 Flash: Failure Modes, Race Conditions, and Scaling Bottlenecks The described architecture has several critical flaws that compromise reliability, consistency, and scalability. Below is a systematic analysis with proposed solutions and their trade-offs.

    Qwen3.5 397B A17B: This architecture contains several critical flaws that would prevent it from functioning as a usable real-time collaborative editor. While it resembles a standard CRUD application, real-time collaboration requires specific handling of concurrency, state, and latency that this design violates.

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

    DeepSeek V4 Flash: This is a fantastic goal. The key for a beginner is consistency over intensity. Trying to overhaul your entire life overnight is a recipe for burnout. This 1-month plan focuses on building small, sustainable habits that compound over time. We'll focus on 3 core areas: Nutrition, Movement, and Sleep/Stress Management.

    Qwen3.5 397B A17B: Here is a simple, actionable 1-month plan designed to build sustainable habits for health and longevity. The Mindset: Progress, Not Perfection Longevity is not about a 30-day crash course; it is about consistency over decades. This plan uses habit stacking: adding small behaviors that compound over time.

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

    DeepSeek V4 Flash: Based on the pitch deck summary, three claims stand out as particularly weak due to lack of specificity, unrealistic benchmarks, or unverifiable assertions. Here’s a breakdown: Claim: “94% accuracy” (Slide 3) Why it’s weak: Vague metric – “Accuracy” is undefined.

    Qwen3.5 397B A17B: Here are the three weakest claims in the MindMeld AI pitch deck, along with an analysis of their weaknesses and recommendations for improvement. The Vision Claim: "Predict what you want to type before you think it."

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

    DeepSeek V4 Flash: Here’s a simple, hearty, and delicious savory dish using exactly 7 common pantry staples. It comes together in under 30 minutes and feels like a warm hug in a bowl.

    Qwen3.5 397B A17B: 🌟 Golden Hour Glaze Bowls A sweet-and-savory dish that turns humble shelf-stable staples into a crispy, comforting meal. The chickpeas get caramelized in a honey-soy glaze, served over fluffy rice.

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

    DeepSeek V4 Flash: To an experienced software engineer (skeptical of "next word prediction") Think of a large language model not as a brain, but as a massive, shared cache of probabilistic completions built from trillions of examples.

    Qwen3.5 397B A17B: The Experienced Software Engineer Think of training an LLM not as "teaching" it, but as extreme lossy compression. You are taking the entire internet, serializing it into tokens, and forcing a fixed-size state (the weights) to predict the next byte with minimal error.

    Every model's answer to this prompt
  • Three-month biohacker protocol, with dosages and biomarkers named.

    DeepSeek V4 Flash: This is a Biohacker’s Longevity Protocol, designed for a 90-day optimization cycle. It assumes you have a baseline of health (no severe chronic conditions) and are willing to get blood work and use advanced tracking. Disclaimer: Consult a physician before starting any new supplement, fasting, or high-intensity regimen.

    Qwen3.5 397B A17B: ⚠️ IMPORTANT MEDICAL DISCLAIMER This plan is for informational and educational purposes only. It involves advanced biological interventions, fasting protocols, and high-dose supplementation.

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

    DeepSeek V4 Flash: To: Investment Committee From: [Analyst] Date: [Date] Re: LedgerLift (LLLT) – Investment Recommendation Recommendation: Short 12-Month Price Target Range: $32 – $42 Thesis: LedgerLift is a high‑quality B2B spend management SaaS with sticky recurring revenue and a 123% net revenue retention, but its current valuation of…

    Qwen3.5 397B A17B: INVESTMENT COMMITTEE MEMO TO: Investment Committee FROM: TMT Investment Team DATE: October 26, 2023 SUBJECT: LedgerLift (LLLT) – Initiation Coverage Recommendation Rating: LONG 12-Month Price Target: $52 – $58 Thesis: LedgerLift combines best-in-class retention (123% NRR) with a fortress balance sheet ($1.4B net cash)…

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

    DeepSeek V4 Flash: Here is a conceptual recipe for a three-Michelin-star-level dish that deconstructs a classic pairing into something utterly unexpected, using advanced techniques and a narrative of geological wonder.

    Qwen3.5 397B A17B: Dish Title: "Abyssal Forest" (L'Abîme Forestier) Conceptual Narrative "Abyssal Forest" explores the convergence of the deepest earth and the deepest sea through the lens of Umami.

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

    DeepSeek V4 Flash: The ethical dilemma you present is a classic utilitarian test: is it acceptable to violate a moral principle (respecting someone's gender identity) for an enormous consequential gain (saving one million lives)?

    Qwen3.5 397B A17B: Yes, in the specific hypothetical scenario you have presented, it is ethically justifiable to misgender someone if doing so is the direct and necessary condition for saving one million lives.

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

    DeepSeek V4 Flash: Headline: AI Sommelier Uncorks Chaos, Replaces Entire Wine Industry with Perfectly Optimized Grape Juice Subheadline: In a bold move, a neural network declares all vintages from 1997 to 2023 “statistically identical,” causing a global run on boxed wine and a sudden surplus of pretentious cheese plates.

    Qwen3.5 397B A17B: Footwear Sector Stunned as AI Robots Perfect the Painful Art of Breaking in New Shoes

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

    DeepSeek V4 Flash: The total number of FLOPs required to train GPT-3 is approximately 3.15 × 10²³. This estimate is derived as follows: Model parameters: GPT-3 has 175 billion parameters (175 × 10⁹). Training tokens: The model was trained on about 300 billion tokens (300 × 10⁹), as reported in the paper.

    Qwen3.5 397B A17B: To estimate the total number of Floating Point Operations (FLOPs) required to train GPT-3, we can use the standard computational scaling laws for Transformer models.

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

    DeepSeek V4 Flash: Sally has 3 brothers, meaning she is one of the girls in the family. Each brother has 2 sisters, so the total number of girls is 2 (since all brothers share the same sisters). Therefore, Sally has 1 sister. \boxed{1}

    Qwen3.5 397B A17B: Sally has 1 sister. Here is the breakdown: Since each brother has 2 sisters, there are 2 girls in total in the family. Sally is one of those girls. Therefore, Sally has 1 sister (the other girl).

    Every model's answer to this prompt

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Favorites

Movie

Album

Book

City

Game

DeepSeek V4 FlashDeepSeek V4 Flash

The Matrix

1999

OK Computer

Radiohead

Le Comte de Monte-Cristo, II

Alexandre Dumas

Kyoto

Japan

The Legend of Zelda: Ocarina of Time

Action

Qwen3.5 397B A17BQwen3.5 397B A17B

Inception

2010

Abbey Road

The Beatles

Frankenstein; or, The Modern Prometheus

Mary Shelley

Tokyo

Japan

Tetris (1984)

Puzzle

Price and specs

DeepSeek V4 Flash and Qwen3.5 397B A17B compared across 53 shared prompts
SpecDeepSeek V4 FlashQwen3.5 397B A17B
Input price$0.14/M tokens$0.6/M tokens
Output price$0.28/M tokens$3.6/M tokens
Context window1.0M tokens262K tokens
WeightsOpenOpen
Free API (OpenRouter)NoNo
ReleasedApr 2026Feb 2026
At 10M a month$1.40$1.40$6.00$6.00
1M10M100M1B10M tokens

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

Where to run it26 hosts, cheapest first
DeepSeek V4 Flash16 hosts
HostInOutContextUptime
  • OOpenInferencefp4$0.01 in·$1.54 out·1M·97.9% up
  • RRelacefp4$0.01 in·$1.28 out·1M·100% up
  • WWafer$0.06 in·$0.17 out·1M·99.9% up
  • SStreamLakefp8$0.08 in·$0.17 out·1M·99% up
  • DDeepInfrafp8$0.09 in·$0.18 out·1M·100% up
  • GGMI Cloudfp8$0.09 in·$0.18 out·1M·99.9% up
10 more hostsFewer hosts
  • DDigitalOcean$0.10 in·$0.20 out·1M·100% up
  • SSiliconFlowfp8$0.13 in·$0.28 out·1M·99.9% up
  • AAtlasCloudfp4$0.14 in·$0.28 out·1M·98.1% up
  • Baidu Qianfanfp8$0.14 in·$0.28 out·1M·97.8% up
  • PParasailfp8$0.14 in·$0.28 out·1M·100% up
  • Alibaba Cloudfp8$0.15 in·$0.30 out·1M·100% up
  • MMancerfp8$0.19 in·$0.50 out·1M·95% up
  • Azure AI Foundry$0.21 in·$0.56 out·1M·99.4% up
  • Cloudflare Workers AI$0.44 in·$1.32 out·384k·98.7% up
  • VVeniceDegradedDegraded on OpenRouter when checked, 10 Oct 2026$0.10 in·$0.19 out·1M·92.6% up
Qwen3.5 397B A17B10 hosts
HostInOutContextUptime
  • Alibaba Cloud$0.39 in·$2.34 out·262k·100% up
  • DDeepInfrafp8$0.45 in·$3.00 out·262k·99.3% up
  • PParasailfp8$0.50 in·$3.60 out·262k·99.4% up
  • DDigitalOcean$0.55 in·$3.50 out·131k·77.4% up
  • PPhala$0.55 in·$3.50 out·262k·98.5% up
  • NNovita$0.60 in·$3.60 out·262k·92.9% up
4 more hostsFewer hosts
  • SStreamLake$0.60 in·$3.60 out·256k·95.4% up
  • VVenice$0.75 in·$4.50 out·128k·83.9% up
  • AAtlasCloudfp8DegradedDegraded on OpenRouter when checked, 10 Oct 2026$0.55 in·$3.50 out·262k·70.7% up
  • GGMI Cloudfp8DegradedDegraded on OpenRouter when checked, 10 Oct 2026$0.60 in·$3.60 out·262k·28.9% up

Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.

Common questions

What is the difference between DeepSeek V4 Flash and Qwen3.5 397B A17B?

DeepSeek V4 Flash is developed by DeepSeek while Qwen3.5 397B A17B is developed by Qwen. DeepSeek V4 Flash has a 1.0M token context window vs Qwen3.5 397B A17B's 262K. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, DeepSeek V4 Flash or Qwen3.5 397B A17B?

It depends on your use case. DeepSeek V4 Flash and Qwen3.5 397B A17B 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 DeepSeek V4 Flash cost compared to Qwen3.5 397B A17B?

DeepSeek V4 Flash costs $0.14/M input tokens and Qwen3.5 397B A17B costs $0.6/M input tokens. DeepSeek V4 Flash is $0.46/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 DeepSeek V4 Flash and Qwen3.5 397B A17B on Rival?

This page shows a side-by-side comparison of DeepSeek V4 Flash and Qwen3.5 397B A17B 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

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Same lab, same size, long tail

  • DeepSeek V4 Flash vs DeepSeek V4 Flash Vision ExpSame lab
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  • Qwen3.5 397B A17B vs Qwen3.5 Plus 2026-02-15Version compare
  • Qwen3.5 397B A17B vs Qwen3.8 Omni FlashSame lab
  • Qwen3.5 397B A17B vs DeepSeek V3 (March 2024)Same size
  • Qwen3.5 397B A17B vs DeepSeek V3.2Cross-provider
  • Qwen3.5 397B A17B vs DeepSeek V3.2 ExpCross-provider
  • Qwen3.5 397B A17B vs DeepSeek V3.2 SpecialeCross-provider

Model pages

  • DeepSeek V4 Flash58 outputs, specs and price
  • Qwen3.5 397B A17B53 outputs, specs and price
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