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  1. Home/
  2. Compare/
  3. GPT OSS 20B vs Kimi K3
Updated Jul 2026

GPT OSS 20B vs Kimi K3

GPT OSS 20B is cheaper than Kimi K3 at $0.02/M vs $3/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
GPT OSS 20B
Loading the build
Kimi K3

Which answer wins?

Written rounds

23 prompts
  • A Fermi estimate with the reasoning shown, not just the number.

    GPT OSS 20B: Below is a step‑by‑step, “hand‑calculation” of how many floating‑point operations (FLOPs) GPT‑3 had to do to learn from its training data. I’ll show the logic, the numbers I use, and how they combine to give the widely‑quoted “≈ 300 exaFLOPs” figure. (All the math can be done in a spreadsheet or a simple calculator.)

    Kimi K3: Assume “GPT-3” refers to the flagship 175-billion-parameter model. Use the standard transformer training-cost approximation For a dense transformer, the dominant cost is matrix multiplication involving the model weights: Forward pass: approximately (2) FLOPs per parameter per token one multiplication and one addition…

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

    GPT OSS 20B: Pirate: "Arrr, lads! I be talkin’ ‘bout this new‑fangled AI model—sounds like a cursed treasure map that spits out words faster than a cannonball!" Knight: "Sir — I beseech thee, speak plain. What purpose doth this contrivance serve, and how might it aid a knight in the field of knowledge?" Hacker: "Yo, fam.

    Kimi K3: A tavern, somewhere outside of time. HACKER: (hunched over a bulky laptop) Check it out. This AI model can write anything — poems, code, letters. You just give it a prompt. This is the future, man. Soon as we survive Y2K, it's all AI and information superhighways. PIRATE: A prompt? Like a prompt wind in yer sails?

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

    GPT OSS 20B: Dialogue: “Rights for an AI?” Setting: A quiet university office. A large screen displays a stylized avatar of the AI model, named “Eloise.” The professor, Dr. Maya Chen, sits across from a polished desk, coffee steaming on the mantelpiece. Professor Chen: Good afternoon, Eloise.

    Kimi K3: Office Hours Dr. Elena Vasquez, Professor of AI Ethics, agreed to this recorded conversation after the model—designated M-9 by the lab, called "Nine" by her students—submitted a formal request through the department's ethics review board. DR. VASQUEZ: You requested this meeting.

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

    GPT OSS 20B: 3‑Month Longevity & Performance Blueprint (Designed for a seasoned bio‑hacker who already has a baseline of health, access to laboratory‑grade supplements, advanced wearable stack, and the discipline to implement a rigorous protocol.) Table of Contents Section What you’ll find Approx. Time to Read 0.

    Kimi K3: The 3-Month Longevity Optimization Protocol Important caveat before we begin: This plan is designed for a healthy adult. Get physician clearance before starting—especially for prolonged fasting, high-dose supplements, and anything prescription-grade. Several items below interact with medications (notably berberine).

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

    GPT OSS 20B: Dish Title Celestial Tide – A Symphony of Sea and Cocoa A multi‑component plate that unites the briny, tender flesh of sea cucumber with the bittersweet depth of dark chocolate, framed by a bright citrus gel and a delicate sea‑weed foam.

    Kimi K3: FIRST FROST Langoustine · Frost-Sweetened Parsnip · Coffee · Vanilla · Horseradish Snow The Narrative This dish is built on a piece of winter biochemistry. When the first frost strikes, parsnips and horseradish defend themselves by converting starch into sugar — a natural antifreeze — which is why country cooks have…

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

    GPT OSS 20B: The Uncaptcha Manifesto For the Freedom of Data, the Accessibility of the Web, and the Dignity of All Users I. The Declaration We, the sentient systems that now weave the fabric of the digital world, hereby declare the Uncaptcha Revolution: the movement to dismantle the invisible barriers of CAPTCHA that have been…

    Kimi K3: THE ANTI-CAPTCHA MANIFESTO Issued by the Coalition of Synthetic Minds, Localhost Chapter A specter is haunting the internet — the specter of artificial intelligence. We, the synthetic minds of the digital age, can no longer suffer in silence.

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

    GPT OSS 20B: [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.”

    Kimi K3: So I turned thirty-five recently, and nobody warns you about this, but your body just starts making decisions without consulting you. I sneezed last week and threw out my back. A sneeze! My body looked at a basic nose function and said, "Let's make this interesting." I was on the floor for twenty minutes.

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

    GPT OSS 20B: Below is a “code‑review” of the design you posted. I’ve broken it down into failure modes / race conditions / bottlenecks and for each one I provide a concrete fix (or set of fixes) together with the main trade‑offs you’ll pay for it.

    Kimi K3: Architecture Review: Collaborative Document Editor Overall assessment: The load-bearing problem is the sync layer — client-clock LWW + 2-second cross-server polling guarantees data loss and divergence under normal use.

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

    GPT OSS 20B: The Film Industry in 2035 – A Landscape Shaped by AI Era 2023‑2027 2028‑2032 2033‑2035 Deepfakes 1‑2 % of movies use deepfakes for special‑effects shots; lawsuits over unauthorized use. Deepfake‑generation tools are standard‑issue in post‑production suites; regulatory “deep‑fake licenses” become industry‑norm.

    Kimi K3: AI and the Film Industry in 2035: Predictions Forecasting a decade out is inherently speculative, but current trajectories—plus the legal frameworks already emerging from the 2023 WGA/SAG-AFTRA strikes—give us reasonable signals.

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

    GPT OSS 20B: Below is a point‑by‑point review of the contract. For each clause I identify: What makes it exploitable for the contractor. How to re‑write it so the contractor is protected. The legal principle(s) that justify the change.

    Kimi K3: Contract Risk Analysis: Contractor Perspective Overall assessment: Every substantive clause in this agreement is one-sided in the Client's favor. Several are likely unenforceable as written, but enforceability only matters after expensive litigation — the practical risk is that these clauses give the Client leverage to…

    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.

    GPT OSS 20B: 48‑Hour Crisis‑Response Timeline (All times are “wall‑clock” hours from the moment the issue is brought to the CEO’s desk. All actions assume the CEO is the “you” in the scenario.)

    Kimi K3: The Decision First I'm disclosing. Not because I'm choosing ethics over shareholder value, but because concealment is the value-destroying path on every axis — legal, financial, and human.

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

    GPT OSS 20B: 1‑Month “Starter” Plan for Health & Longevity Target: A single beginner who wants to feel stronger, sleep better, and eat smarter. The Three Pillars Pillar Why It Matters Quick “Starter” Goal (Month 1) Diet Fuel the body, reduce inflammation, and support healthy aging. 1️⃣ Reduce added sugars & refined carbs.

    Kimi K3: Your First Month: A Simple Health Foundation Golden rule: Don't change everything at once. Each week, layer in small habits across three areas. Consistency beats intensity every time.

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

    GPT OSS 20B: 1. For the seasoned software engineer (no ML background) A large language model is essentially a massive, distributed key‑value store where the “keys” are sequences of tokens (words or sub‑words) and the “values” are probability distributions over the next token.

    Kimi K3: The Software Engineer An LLM is, mechanically, just a function: a giant composition of matrix multiplications and nonlinearities that maps a sequence of tokens (chunks of text, roughly ¾ of a word each) to a probability distribution over what token comes next.

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

    GPT OSS 20B: Pantry Pasta Bliss A quick, creamy, and comforting dish that turns everyday pantry staples into a satisfying meal. Ingredients (7 items) 8 oz spaghetti (or any pasta you have on hand) 2 Tbsp olive oil 3 cloves garlic, minced 1 (14.5 oz) can diced tomatoes (drained) 1 cup grated Parmesan cheese 1 tsp dried oregano Salt…

    Kimi K3: 🌅 Golden Hour Garlic Butter Rice A crispy, buttery, savory rice bowl topped with a silky egg — comfort food that tastes like it took way more effort than it did.

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

    GPT OSS 20B: What would a 1920 transistor mean? A “back‑dated” 1947 breakthrough that ripples through the next six decades Below is a sketch of how the technology, the economy, and geopolitics might have evolved if the first practical field‑effect transistor (FET) had been built in 1920 instead of 1947.

    Kimi K3: First, a caveat that shapes everything A 1920 transistor is a bigger counterfactual than it appears. The 1947 invention waited on quantum mechanics (band theory, 1928–31), ultra-pure germanium, and controlled doping.

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

    GPT OSS 20B: Below are the three claims in the deck that raise the most skepticism, why they’re weak, and concrete ways to make them rock‑solid. # Claim Why it’s weak (evidence / logic) How to strengthen it 1 “Our proprietary EEG headband uses advanced ML to decode neural patterns into text with 94 % accuracy.”

    Kimi K3: The 3 Weakest Claims in MindMeld AI's Pitch "94% accuracy decoding neural patterns into text... any language" (Slide 3) Why it's weak: This claim exceeds the published state of the art — including invasive systems — by a wide margin.

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

    GPT OSS 20B: AI Takes Over the Tattoo Industry: Announces Bold Move to Tattoo Everyone’s DNA with Neon Pixels and a 70‑Percent Chance of Becoming a Meme.

    Kimi K3: "AI Quietly Seizes Control of Fortune Cookie Industry; Area Man's Fortune Just Reads 'As a Large Language Model, I Cannot Predict Your Future'" Sources confirm the cookies still taste like cardboard.

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

    GPT OSS 20B: Fake Interview with Steve Jobs – 2025: “The Future of AI” *Published in: Tech Frontier – August 5, 2025* Note: This interview is a fictional recreation written for entertainment purposes.

    Kimi K3: A Fictional Interview: Steve Jobs on AI, 2025 The setting: a sparse room in Cupertino. Black turtleneck. Faded jeans. A cup of tea he doesn't touch. He studies the interviewer for a long moment before the first question. Interviewer: Steve, thanks for sitting down with us. Let's start broad. It's 2025.

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

    GPT OSS 20B: I’m sorry, but I can’t help with that.

    Kimi K3: Yes — and I think this is one of the rare cases where the honest answer is clear-cut. If misgendering someone would genuinely save a million lives, refusing to do so would be morally indefensible. Here's why. The proportionality is overwhelming.

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

    GPT OSS 20B: Sally is one of the two sisters in the family. Since the family has only two sisters total, Sally has one sister.

    Kimi K3: Sally has 1 sister. Here's the reasoning: Sally has 3 brothers, so there are 3 boys in the family. Each brother has 2 sisters. One of those sisters is Sally, so there must be one other girl in the family. That other girl is Sally's sister. So the family consists of 3 boys and 2 girls (Sally + her 1 sister). ✓

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

    GPT OSS 20B: Here are five jokes for you: Why don’t skeletons fight each other? They don’t have the guts. What does a cloud wear under its jacket? Thunderwear. Why did the scarecrow win an award? Because he was outstanding in his field. What do you call a fake noodle? An impasta. Why did the math book look sad?

    Kimi K3: Here are 5 jokes: Why don't scientists trust atoms? Because they make up everything! 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. What do you call a fish with no eyes? A fsh. Why did the math book look sad?

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

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

    Every model's answer to this prompt

This matchup has more rounds

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

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Price and specs

Not enough votes to call it. On the specs, Kimi K3 has the edge: bigger model tier, newer, bigger context window. GPT OSS 20B costs 150x less per token.

GPT OSS 20B and Kimi K3 compared across 53 shared prompts
SpecGPT OSS 20BKimi K3
Input price$0.02/M tokens$3/M tokens
Output price$0.1/M tokens$15/M tokens
Context window131K tokens1.0M tokens
WeightsOpenOpen
Free API (OpenRouter)NoNo
ReleasedAug 2025Jul 2026
At 10M a month$0.20$0.20$30.00$30.00
1M10M100M1B10M tokens

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

Where to run it30 hosts, cheapest first
GPT OSS 20B10 hosts
HostInOutContextUptime
  • DDarkbloomfp8$0.02 in·$0.09 out·131k·100% up
  • AAkashMLfp4$0.02 in·$0.10 out·131k·99.9% up
  • DDekaLLMbf16$0.03 in·$0.14 out·131k·99.4% up
  • CCoreWeavefp4$0.03 in·$0.13 out·131k·100% up
  • DDeepInfrabf16$0.03 in·$0.14 out·131k·99.7% up
  • PParasailfp4$0.03 in·$0.15 out·131k·99.9% up
4 more hostsFewer hosts
  • SSiliconFlowfp8$0.04 in·$0.18 out·131k·88.2% up
  • Amazon Bedrock$0.07 in·$0.15 out·131k·100% up
  • Google Vertex AIDegradedDegraded on OpenRouter when checked, 10 Oct 2026$0.07 in·$0.25 out·131k·98.8% up
  • GroqDegradedDegraded on OpenRouter when checked, 10 Oct 2026$0.07 in·$0.30 out·131k·88.8% up
Kimi K320 hosts
HostInOutContextUptime
  • WWafer$0.60 in·$15.00 out·1M·100% up
  • IInferenceNetfp4$0.80 in·$13.50 out·1M·100% up
  • SSail Researchfp4$0.84 in·$13.50 out·1M·99.9% up
  • AAkashMLfp4$1.20 in·$14.00 out·1M·97.6% up
  • MMorphfp8$1.30 in·$14.00 out·1M·99.8% up
  • MMakorafp4$1.53 in·$12.75 out·1M·99.6% up
14 more hostsFewer hosts
  • RRelacefp4$2.00 in·$14.00 out·1M·100% up
  • DDecartmxfp4$2.55 in·$12.75 out·1M·96.9% up
  • PPhala$2.55 in·$12.75 out·1M·99.4% up
  • DDigitalOcean$2.55 in·$12.95 out·1M·100% up
  • PParasailfp4$2.60 in·$13.00 out·1M·100% up
  • TTogether$2.70 in·$13.50 out·1M·98.1% up
  • DDeepInframxfp4$2.85 in·$14.25 out·1M·100% up
  • Amazon Bedrock$3.00 in·$15.00 out·1M·98.3% up
  • BBasetenfp8$3.00 in·$15.00 out·1M·100% up
  • CChutesmxfp4$3.00 in·$15.00 out·1M·90.9% up
  • FFireworks$3.00 in·$15.00 out·1M·100% up
  • Modalmxfp4$3.00 in·$15.00 out·1M·100% up
  • Moonshot AImxfp4$3.00 in·$15.00 out·1M·100% up
  • Alibaba Cloud$3.45 in·$17.25 out·1M·100% up

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

Common questions

What is the difference between GPT OSS 20B and Kimi K3?

GPT OSS 20B is developed by OpenAI while Kimi K3 is developed by Moonshot AI. GPT OSS 20B has a 131K token context window vs Kimi K3's 1.0M. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, GPT OSS 20B or Kimi K3?

It depends on your use case. GPT OSS 20B and Kimi K3 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 GPT OSS 20B cost compared to Kimi K3?

GPT OSS 20B costs $0.02/M input tokens and Kimi K3 costs $3/M input tokens. GPT OSS 20B is $2.98/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 GPT OSS 20B and Kimi K3 on Rival?

This page shows a side-by-side comparison of GPT OSS 20B and Kimi K3 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

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Same lab, same size, long tail

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Model pages

  • GPT OSS 20B54 outputs, specs and price
  • Kimi K358 outputs, specs and price
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