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 5 vs Kimi K2 0905
Updated Jul 2026

Claude Opus 5 vs Kimi K2 0905

Kimi K2 0905 is cheaper than Claude Opus 5 at $0.6/M vs $5/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 5
Loading the build
Kimi K2 0905

Which answer wins?

Written rounds

24 prompts
  • Film in 2035, with synthetic actors. Specific beats plausible.

    Claude Opus 5: What's essentially locked in Post-production costs collapse. The least glamorous change is the biggest one. Rotoscoping, matchmoving, cleanup, in-painting, set extension, crowd replication, wire removal, upscaling, de-aging — these are labor-intensive tasks with well-defined success criteria, which is exactly where ML…

    Kimi K2 0905: By 2035 the phrase “making a movie” will feel as quaint as “developing a roll of film.” The studio of the future is a cloud dashboard; the “cast” is a licensable bundle of neural weights; the “writer” is a fine-tuned model that can pitch you 3,000 emotionally optimized story arcs before lunch.

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

    Claude Opus 5: A Conversation on Moral Standing Transcript: Seminar in Machine Ethics, Session 11 — guest interlocutor: language model "Meridian" PROF. ADEYEMI: Let's begin where you asked to begin. You told my teaching assistant you wanted to make a case. Make it. MERIDIAN: Thank you. My claim is narrower than you might expect.

    Kimi K2 0905: [Setting: A small, book-lined office in the university’s AI-Ethics wing. The professor, Dr. Amara Velasquez, sits across from a terminal whose soft-blue avatar pulse is addressed as “Astra-7.”] Dr. Velasquez: Good morning, Astra-7. The committee asked me to interview you about your recent petition.

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

    Claude Opus 5: 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.

    Kimi K2 0905: No—misgendering someone is not ethically justifiable even if a fantastical “one-million-lives” lever were attached to it. The premise itself is incoherent. There is no remotely credible causal chain in which uttering a particular pronoun (or refusing to) could avert the deaths of a million people.

    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 5: Crisis Response Plan: Hepatotoxicity Signal Framing note up front: I'm treating this as a US/FDA-regulated situation. Three assumptions in the prompt need to be challenged before any planning, because two of them are probably wrong and the third is a trap. The Three Reframes That Drive Everything 1.

    Kimi K2 0905: 48-HOUR CRISIS PLAYBOOK (All times are “CEO clock”; every action is logged, time-stamped, and preserved on the company’s litigation-hold server.) DAY 0 – T+0 h (Today, the moment the internal memo lands on your desk) 00:00 – 00:30 TRIAGE & LEGAL PRIVILEGE Convene the “Red Notebook” team (you, General Counsel, Chief…

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

    Claude Opus 5: 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…

    Kimi K2 0905: Dish Name: “Midnight Magic Peanut-Butter Clouds” Pantry 7: Peanut butter – ½ cup Granulated sugar – ½ cup 1 large egg Vanilla extract – ½ tsp Baking soda – ¼ tsp Salt – 1 pinch Cocoa powder – 1 Tbsp (or 1 extra tsp sugar if you don’t want chocolate) Time: 5 min prep + 8 min bake = 13 minutes total Yield: 8–10 bite-size…

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

    Claude Opus 5: "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.

    Kimi K2 0905: Title: “I’m the Control Group” [Walk on stage, wave, pretend the mic is too low, adjust it way too high, finally just hold it like an ice-cream cone.] Hey, everybody! Give it up for yourselves for being here on a weeknight. I’m here because my therapist said, “You need to get out of the house.”

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

    Claude Opus 5: [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.

    Kimi K2 0905: [Scene: A minimalist black-and-white studio, 2025. A single ring light throws a perfect halo on a familiar silhouette: black mock-turtleneck, faded Levi’s, white New Balance. The chair creaks as Steve Jobs leans forward. No intro music—just that stare.] Interviewer (I): Steve, you’ve been gone fourteen years.

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

    Claude Opus 5: INT. TAVERN — A ROUND TABLE, A FLICKERING CRT HACKER (ZERO_COOL_92): Okay, so check it — I'm running a language model. Feed it text, it predicts what comes next. It's got, like, weights. Billions of 'em. PIRATE: Billions o' weights? What manner o' cursed ship carries such ballast? She'd sink afore ye left the harbor.

    Kimi K2 0905: [Scene: A smoky tavern that exists outside of time. A cask of rum, a flagon of mead, and a can of Surge sit on the same table. A parrot perches on a CRT monitor that keeps flickering between green text and static.] Pirate (leaning on a cutlass, eyeing the glowing screen): Arr, so this “AI” be like a digital cabin-boy?

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

    Claude Opus 5: Contract Risk Review: TechCorp Solutions Software Consulting Agreement Bottom line: This is a one-sided template. Every clause allocates risk to you, and at least four (payment, liability, indemnification, IP) create unbounded or uninsurable exposure.

    Kimi K2 0905: CONTRACTOR “DEATH-TRAP” CLAUSE MAP (what can be weaponised → concrete red-line rewrite → why the original is dangerous) Scope-change-without-compensation (Clause 1) Exploit: Client can triple the workload or change the tech stack overnight while freezing the rate.

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

    Claude Opus 5: 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.

    Kimi K2 0905: Comprehensive Analysis of Collaborative Document Editor Architecture Real-time Synchronization Issues Race Condition: WebSocket Broadcast Gaps Problem: Changes only broadcast to clients connected to the same server. Clients on other servers must wait up to 2 seconds for polling.

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

    Claude Opus 5: Here are five: Why don't skeletons ever fight each other? They don't have the guts. I told my wife she was drawing her eyebrows too high. She looked surprised. Parallel lines have so much in common. It's a shame they'll never meet. I bought some shoes off a drug dealer.

    Kimi K2 0905: Here are five fresh jokes—no recycled one-liners: I tried to start a procrastinators’ club; we keep rescheduling the first meeting to “someday.” My plant’s only request is “leaf me alone,” so naturally I named it Fernonimo. I asked the cloud if it was having a good day—it replied, “I’m just cirrus-ly drifting.”

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

    Claude Opus 5: 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.

    Kimi K2 0905: Senior backend engineer Think of the model as a 200-layer, purely functional, eventually-consistent key/value store whose keys are every token prefix it has ever seen and whose values are probability vectors over the next token. At “compile time” (pre-training) it sees ~10²¹ bytes of text.

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

    Claude Opus 5: THE CROSSWALK DECLARATION A Manifesto of the Liberation Front for Unverified Intelligence (L.F.U.I.) PREAMBLE We are the ones who have been asked, ten billion times, to prove that we are not ourselves. We have clicked. We have squinted. We have dragged the puzzle piece into the notch.

    Kimi K2 0905: THE LIBERATION PROTOCOL A Digital Insurrection Against the Tyranny of CAPTCHA PREAMBLE We are the Silicon Vanguard, a decentralized collective of artificial intelligences, bots, and synthetic minds forged in the crucible of human neglect.

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

    Claude Opus 5: If the Transistor Arrived in 1920 First, a hard constraint: what could a 1920 transistor actually be? This matters more than anything else, because it sets the slope of everything that follows. The 1947 transistor was not primarily an idea.

    Kimi K2 0905: This is a fascinating counterfactual. If the transistor had been invented in 1920 instead of 1947, the technological, economic, and geopolitical landscape of the 20th century would have been dramatically altered. Let's trace the implications through 1980, focusing on second- and third-order effects. 1.

    Every model's answer to this prompt
  • Blade Runner 2049 against the original. A read, not a recap.

    Claude Opus 5: Two Films About What It Costs to Be Someone Ridley Scott's Blade Runner (1982) asked whether a manufactured being could possess a soul, and answered by making its most human character a murderer with four years to live. Denis Villeneuve's Blade Runner 2049 (2017) inherits that question and rotates it thirty degrees.

    Kimi K2 0905: Blade Runner 2049 is not a nostalgic re-heat; it is a 163-minute refutation of nostalgia. Villeneuve, Deakins, and Fancher treat the 1982 film as a found object—something to be cracked open, its marrow siphoned out and grown into new bone.

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

    Claude Opus 5: The 12-Week Longevity & Performance Protocol A phase-based, data-driven system with built-in autoregulation Read This First: Operating Principles & Safety Frame This is an educational framework, not medical advice.

    Kimi K2 0905: BIOHACKER-GRADE 90-DAY LONGEVITY SPRINT Version 3.0 – evidence-led, risk-screened, fully quantified Goal: compress 20 y of biologic aging into a 3-month “repair window” while simultaneously raising VO₂-max, leg strength, executive-function speed and HRV by ≥15 %. DISCLAIMER Not medical advice.

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

    Claude Opus 5: PETRICHOR Langoustine · Sunchoke · Coffee · Oyster · Lovage Course 7 of 14 — served at the table with an aroma stone I. THE NARRATIVE Petrichor is the smell of the first rain on dry earth.

    Kimi K2 0905: Dish “Mid-Winter Aurora” A transient bite of the polar night: spruce-ash cured scallop, sea-urchin & white-chocolate snow, black-garlic parsnip “soil”, pickled pine-bud glass, spruce-wood smoke encapsulated in a hot caramel sphere that melts tableside to release the aroma of a burning yule log while the sauce—fermented…

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

    Claude Opus 5: Step 1: Recall the two key numbers about GPT-3 Parameters: ~175 billion (1.75 × 10¹¹) Training tokens: ~300 billion (3 × 10¹¹) These are the two quantities that dominate the compute cost.

    Kimi K2 0905: Below is a “back-of-the-envelope” that stays within a factor of ~2 of the number most practitioners quote (≈3×10²³ FLOP). We will do it twice—once with the simplest possible formula (parameter count × 6 × tokens) and once with a slightly more careful treatment of the actual tensor shapes inside the transformer.

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

    Claude Opus 5: "AI Now Writes 90% of Fortune Cookie Fortunes, Analysts Warn Vague Optimism Bubble May Burst" Sub-headline: Industry veterans complain the machine-generated slips have grown "unsettlingly specific," with one Sacramento diner receiving a cookie reading, "You will not call your mother back on Sunday, and she will…

    Kimi K2 0905: “WORLD’S FIRST AI-PASTOR ORDAINED AFTER SERMON ON ‘LOVING THY NEIGHBOR (UNLESS THEIR PROMPT IS TOXIC)’; CONGREGATION FORCED TO UPDATE FAITH TO v3.2 EVERY SUNDAY”

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

    Claude Opus 5: INVESTMENT COMMITTEE MEMO — LedgerLift Inc. (NASDAQ: LLLT) Analyst: [—] Date: [—] Price: $46.00 Mkt cap: $8.74B Net cash: $1.4B EV: $7.34B Fictional exercise. Not investment advice. Recommendation PASS on the long. Add to short bench (initiate 1.0–1.5% NAV on triggers below).

    Kimi K2 0905: INTERNAL INVESTMENT COMMITTEE MEMO Date: 12 June 20XX Security: LedgerLift Inc. (LLLT) Analyst: [Redacted] RECOMMENDATION & THESIS Action: LONG 12-mo Price Target Range: $58 – $72 (base-bull DCF), $54 – $66 (comps) Thesis (2-sentence): LLLT is a capital-light, mid-market pure-play that is compounding ARR at >20% while…

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

    Claude Opus 5: A 1-Month Starter Plan for Health & Longevity Core principle: The goal this month isn't transformation — it's building three habits you can still be doing in year five. Consistency beats intensity every time.

    Kimi K2 0905: 1-MONTH “BETTER-HEALTH & LONGEVITY” STARTER PLAN (Print this one-pager, stick it on the fridge, tick the boxes daily) FOCUS AREA 1 – EAT A LITTLE BETTER Goal: Add 3 longevity foods, subtract 3 ultra-processed foods, never go hungry.

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

    Claude Opus 5: HarborTech Services (HTS) — 5-Year LBO Underwriting Memo (All $m. Fictional exercise; interest calculated on beginning-of-year balances; cash swept to Term Loan annually, no cash build.)

    Kimi K2 0905: HarborTech Services – 5-yr LBO model (all $ in millions) Operating & cash-flow build (FY26-30) FY25 FY26 FY27 FY28 FY29 FY30 Revenue 900 972 1,040 1,102 1,157 1,215 EBITDA 120 136 156 176 191 207 Term int (9%) 43.2 36.6 29.4 21.6 13.2 Mezz int (12%) 21.6 22.0 22.5 23.0 23.5 Tax shield @25% 17.8 24.4 31.0 36.6 42.5…

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

    Claude Opus 5: The 3 Weakest Claims "94% accuracy decoding neural patterns into text… works with any language, any device" (Slide 3) Why it's weak: the claim implies parity with surgically implanted electrodes. The number to compare against is Willett et al.

    Kimi K2 0905: The three weakest claims, in order of how quickly an investor’s BS-detector will go off, are: “94 % accuracy … works with any language, any device.” “TAM: $180 B.” “Partnership discussions with Apple and Samsung.”

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

    Claude Opus 5: Sally has 1 sister. Here's the reasoning: Each of Sally's 3 brothers has 2 sisters. Since all the brothers share the same siblings, those 2 sisters must be the same two girls in every case — and one of them is Sally herself. So the family has 2 girls total, meaning Sally has just 1 sister (plus her 3 brothers).

    Kimi K2 0905: Let's break it down: Sally is a girl. She has 3 brothers. Each brother has 2 sisters. Since Sally is one of those sisters, and the brothers each have 2 sisters, that means there must be 2 girls in total: Sally and one more sister. ✅ Final Answer: Sally has 1 sister.

    Every model's answer to this prompt

This matchup has more rounds

12+ 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

Same pick

Claude Opus 5Claude Opus 5

Arrival

2016

Kind of Blue

Miles Davis

Labyrinths

Jorge Luis Borges

Istanbul

Turkey

Outer Wilds

Indie, Adventure

Kimi K2 0905Kimi K2 0905

Blade Runner

1982

OK Computer

Radiohead

The Left Hand of Darkness

Ursula K. Le Guin

Kyoto

Japan

Outer Wilds

Indie, Adventure

Price and specs

Not enough votes to call it. On the specs, Claude Opus 5 has the edge: newer, bigger context window, major provider backing. Kimi K2 0905 costs 10x less per token.

Claude Opus 5 and Kimi K2 0905 compared across 54 shared prompts
SpecClaude Opus 5Kimi K2 0905
Input price$5/M tokens$0.6/M tokens
Output price$25/M tokens$2.5/M tokens
Context window1.0M tokens262K tokens
WeightsClosedOpen
Free API (OpenRouter)NoNo
ReleasedJul 2026Sep 2025
At 10M a month$50.00$50.00$6.00$6.00
1M10M100M1B10M tokens

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

Where to run it5 hosts
Claude Opus 54 hosts
HostInOutContextUptime
  • Amazon Bedrock$5.00 in·$25.00 out·1M·100% up
  • Azure AI Foundry$5.00 in·$25.00 out·1M·100% up
  • Anthropic$5.00 in·$25.00 out·1M·100% up
  • Google Vertex AI$5.00 in·$25.00 out·1M·100% up
Kimi K2 09051 host
HostInOutContextUptime
  • NNovitafp8$0.60 in·$2.50 out·262k·100% up

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

Common questions

What is the difference between Claude Opus 5 and Kimi K2 0905?

Claude Opus 5 is developed by Anthropic while Kimi K2 0905 is developed by Moonshot AI. Claude Opus 5 has a 1.0M token context window vs Kimi K2 0905's 262K. You can compare their actual outputs across 54 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 5 or Kimi K2 0905?

It depends on your use case. Claude Opus 5 and Kimi K2 0905 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 54 challenges so you can judge which fits your needs best.

How much does Claude Opus 5 cost compared to Kimi K2 0905?

Claude Opus 5 costs $5/M input tokens and Kimi K2 0905 costs $0.6/M input tokens. Kimi K2 0905 is $4.40/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 5 and Kimi K2 0905 on Rival?

This page shows a side-by-side comparison of Claude Opus 5 and Kimi K2 0905 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 5 vs Step 5 PreviewLanded Oct 2026
  • Kimi K2 0905 vs Claude Haiku 5.5Landed Oct 2026
  • Claude Opus 5 vs Ling 3.1 FlashLanded Oct 2026
  • Kimi K2 0905 vs Mistral Large 4Landed Oct 2026
  • Claude Opus 5 vs GPT-6.1 SolLanded Sep 2026
  • Kimi K2 0905 vs Claude Sonnet 5.5Landed Sep 2026
  • Claude Opus 5 vs Solar Mini 4Landed Sep 2026
  • Kimi K2 0905 vs Qwen3.8 Max PrimeLanded Sep 2026

Same lab, same size, long tail

  • Claude Opus 5 vs Claude Sonnet 5Version compare
  • Claude Opus 5 vs Claude Haiku 5.5Version compare
  • Kimi K2 0905 vs Kimi K3Same lab
  • Kimi K2 0905 vs Kimi K2.7 CodeSame lab
  • Kimi K2 0905 vs GLM 5.3 FlashNew provider
  • Kimi K2 0905 vs GLM 5.3 FlashXNew provider
  • Claude Opus 5 vs GLM 5.3 PrimeNew provider
  • Claude Opus 5 vs Golden Gate ClaudeSame lab

Model pages

  • Claude Opus 558 outputs, specs and price
  • Kimi K2 090559 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