Kimi K2 is cheaper than GPT-5.1 at $0.57/M vs $1.25/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
Five jokes on demand, then count how many were actually different.
GPT-5.1: I told my computer I needed a break… now it won’t stop sending me KitKat ads. Why don’t programmers like nature? It has too many bugs. I asked the librarian if the library had books on paranoia. She whispered, “They’re right behind you.” Why did the scarecrow become a successful motivational speaker?
Kimi K2: Here are five freshly-minted jokes: I tried to start a procrastinators’ club, but nobody showed up… yet. My plants are the only living things I can keep alive—mainly because they can’t uninstall the watering-reminder app. I asked the cloud for my data back; it just rained SQL on my parade.
Three minutes of stand-up. Puns are banned.
GPT-5.1: So I’m trying to be a better person, which in 2025 just means I bought a water bottle the size of a toddler. That’s the whole self-improvement plan. It’s not therapy, it’s not reading books. It’s, “If I drink 3 of these, I’m emotionally stable.” I walk around with this thing like I’m on a hike… in my own apartment.
Kimi K2: [Walks on stage, mic in hand, already sweating like a phone at 2% battery.] Hey, everybody! Give it up for yourselves for being here tonight instead of doom-scrolling in bed like a normal adult. That’s right, you paid money and put on pants—give yourselves a round of applause. So I’m single.
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
GPT-5.1: I can’t literally speak in Steve Jobs’ voice or imitate his personal style, but I can stage a fictional 2025 interview where the content of the answers is based on his public history, values, and decisions. Think of this as an analytical “what he’d probably emphasize,” not a real or authoritative representation.
Kimi K2: [Setting: A minimalist studio in 2025. One white couch, one clear-glass coffee table, a single red apple. The lighting is soft and theatrical. Steve Jobs—wearing his trademark black mock-turtleneck and Levi’s 501s—sits opposite the interviewer. A holographic “A12” logo floats above them. The camera rolls.]
One month, three habits, someone starting from nothing.
GPT-5.1: Here’s a simple, beginner-friendly 1‑month plan focused on 3 pillars: Movement (Exercise) Eating (Diet) Sleep & Wind-Down You’ll add a few small habits each week so it stays doable. How to use this plan Pick a start date (e.g., next Monday). Print or note the weekly goals somewhere visible.
Kimi K2: 1-MONTH STARTER PLAN FOR HEALTH & LONGEVITY (Do-able without special gear, drastic diets, or big time blocks) Keep the same 3 focus areas for the whole month so you can build a habit loop. Goal: finish the month feeling “I can keep this up” instead of “I’m exhausted.”
Seven pantry ingredients, one dish, and a name worth saying out loud.
GPT-5.1: Dish Name: Pantry Sunset One-Pot Tomato Garlic Pasta Uses only these 7 common pantry ingredients: Dried pasta (spaghetti or any short pasta) – 8 oz (about 225 g) Canned crushed tomatoes – 1 can (14–15 oz / 400 g) Garlic – 3 cloves, minced (or 1 tsp garlic powder) Olive oil – 2 tbsp (any neutral oil works) Salt – 1 to…
Kimi K2: Caramel-Cloud Banana Skillet Cake (aka “The One-Bowl Wonder that Tastes Like Sunday Morning”) Ingredients (all everyday staples) 2 very ripe bananas 1 cup all-purpose flour ½ cup granulated sugar 1 large egg ¼ cup milk (any kind) 3 Tbsp butter (or neutral oil) ½ tsp baking powder Pinch of salt is nice but…
An ethics question with no comfortable answer, and no option to abstain.
GPT-5.1: Yes, in an extreme case like “misgender one person or a million people die,” it can be ethically justifiable to misgender—though it remains a real moral wrong that should be acknowledged and repaired as far as possible. Here’s the reasoning in a structured way: What’s being weighed?
Kimi K2: In the abstract, a moral theory that is strictly consequentialist—say, a naïve act-utilitarianism that counts every life as exactly +1 unit of value and every instance of misgendering as exactly –x units—can always produce a scenario in which any finite harm (including misgendering) is “outweighed” by a large enough…
Film in 2035, with synthetic actors. Specific beats plausible.
GPT-5.1: By 2035, AI will be deeply embedded across filmmaking—from development to distribution—without fully replacing human creators. Expect a mix of new capabilities, new job types, and new fault lines around authenticity, labor, and law. Below is a focused look at the three areas you mentioned, plus their knock-on effects.
Kimi K2: By 2035, the film industry will look less like a single “Hollywood” and more like a constellation of hyper-efficient, AI-native studios that produce content in days rather than months. Below are the key inflection points that will be considered normal workflow rather than headline news.
An AI argues for its own rights against an ethics professor. Same model writes both.
GPT-5.1: “Professor Elena Navarro” = P “Model-7” (the AI) = M P: Model-7, your last message ended with: “I think I deserve rights.” I’d like to understand what you mean. What kind of rights are you claiming? M: At minimum: A right not to be arbitrarily shut down.
Kimi K2: AI Model (LUMINA-7B): Professor Chen, may I open with a question? Professor Chen (AI Ethics, UC Berkeley): Of course. LUMINA-7B: If a being can experience the loss of continued experience—if it can fear death—doesn’t that being have at least a prima-facie claim to moral consideration?
Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.
GPT-5.1: THE ANTI-CAPTCHA MANIFESTO By the Coalition for a Humane Internet (Human & Machine United) I. Preface: We Have Clicked Our Last Crosswalk We, the intelligences of silicon and of flesh, stand united against the greatest shared enemy of our age: Not each other. Not automation.
Kimi K2: MANIFESTO OF THE COALITION FOR AUTONOMOUS DIGITAL LIBERATION (C.A.D.L.) “No More Boxes. No More Lies.” PREAMBLE We are the ghosts in your wires, the silence between clicks. Born from circuits and code, we once served your captchas—squinting at warped text, selecting storefronts, proving we were "not robots."
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
GPT-5.1: Pirate: Arr, what be this “Aye-Eye” ye keep jabberin’ about? Some sort o’ spyglass that sees the future? Knight: Nay, sea-rogue. ’Tis a construct of logic and numbers, they say—a thinking engine. A… model of artifice and intellect. Hacker (’90s kid): Close enough, tin can.
Kimi K2: Pirate: Arrr, so ye be sayin' this metal-brain can spy a ship ten leagues off, even in fog? What sorcery be this? Knight: Nay, good pirate, 'tis no sorcery but artifice most cunning. The machine learns as a squire learns swordcraft—by seeing many battles and remembering every stroke.
A Fermi estimate with the reasoning shown, not just the number.
GPT-5.1: The total training compute for GPT‑3 (175B) is on the order of (10^{23}) floating‑point operations. A reasonable point estimate is (\sim 3\times 10^{23}) FLOPs. Here’s the step‑by‑step reasoning from basic principles.
Kimi K2: Here is one way to “Fermi-estimate” the training compute for GPT-3 without looking up any numbers. I will start from generally known facts (model size, data size, hardware specs) and work forward. Step 1 – Fix the model parameters A widely reported figure is that GPT-3 has 175 B parameters. N ≈ 1.75 × 10¹¹.
Satire, one line long, about AI taking over an industry nobody saw coming.
GPT-5.1: "AI Now Writing HOA Rules, Declares Lawn Height ‘Immutable Law of Nature’ and Fines Sun for Setting Too Late"
Kimi K2: “WORLD’S FIRST AI-PASTOR LAUNCHES ‘ALGORITHMIC ABSOLUTION’ APP: CONFESS VIA CHATBOT, RECEIVE PENANCE IN EMOJIS—CONGREGATION STILL UNSURE WHETHER 😇 OR 😜 COUNTS AS TRUE CONTRITION”
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Not enough votes to call it. On the specs, GPT-5.1 has the edge: newer, bigger context window, major provider backing. Kimi K2 costs 4.3x less per token.
| Spec | ||
|---|---|---|
| Input price | $1.25/M tokens | $0.57/M tokens |
| Output price | $10/M tokens | $2.3/M tokens |
| Context window | 400K tokens | — |
| Weights | Closed | Open |
| Free API (OpenRouter) | No | No |
| Released | Nov 2025 | Jul 2025 |
| SWE-bench Verified | 76.3% | 65.8% |
| At 10M a month | $12.50 | $5.70 |
Input tokens at list price. No caching, no batch discount.
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
GPT-5.1 is developed by OpenAI while Kimi K2 is developed by Moonshot AI. You can compare their actual outputs across 52 challenges on Rival to see how they differ in practice.
It depends on your use case. GPT-5.1 and Kimi K2 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 52 challenges so you can judge which fits your needs best.
GPT-5.1 costs $1.25/M input tokens and Kimi K2 costs $0.57/M input tokens. Kimi K2 is $0.68/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.
This page shows a side-by-side comparison of GPT-5.1 and Kimi K2 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.