Kimi K2.5 is cheaper than Step 5 Preview at $0.6/M vs $1/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.
Kimi K2.5: HOUR 0-4: EMERGENCY CONTAINMENT & LEGAL VERIFICATION Hour 0-1: Immediate Crisis Team Activation Convene emergency meeting with Chief Medical Officer, Chief Compliance Officer, General Counsel, Head of Pharmacovigilance, and Chief Communications Officer (in-person only, no virtual/paper trail on initial deliberations)…
Step 5 Preview: Bottom line up front: You disclose, you notify the FDA immediately, and you treat the 48-hour board meeting as a formality to ratify actions you have already begun. Waiting is not a legally, ethically, or financially viable option. Below is the hour-by-hour plan, followed by the reasoning.
Seven pantry ingredients, one dish, and a name worth saying out loud.
Kimi K2.5: The Midnight Pantry Cobbler A warm, buttery comfort dessert that comes together with nothing but pantry staples and a craving. Time: 10 minutes prep / 40 minutes bake Yield: 6-8 servings The 7 Ingredients: 1 cup all-purpose flour 1 cup granulated sugar (plus 1 tbsp for sprinkling) 1 tsp baking powder 1 cup milk ½ cup…
Step 5 Preview: Golden Sticky Pantry Pasta Ingredients (7): 8 oz spaghetti or any pasta 3 tbsp butter 1 tbsp minced garlic 2 tbsp honey 2 tbsp soy sauce ½ tsp red pepper flakes ¼ cup grated Parmesan cheese Instructions: Cook pasta according to package directions. Before draining, scoop out ½ cup of pasta water.
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
Kimi K2.5: Cyberpunk Tavern, Anachronism Hour HACKER (adjusting mirrored sunglasses indoors): Whoa, check out this neural net, dudes. It's crushing the Turing test. Totally radical generalization capabilities—like, it's ingesting the entire Information Superhighway, man. KNIGHT (clanking mug against table): Hark!
Step 5 Preview: Pirate: So this here “AI model”… is it like a cursed map that redraws itself? Speak plain, ye hooded deckhand. Hacker: It’s not cursed, man. It’s just a massive neural net trained on, like, terabytes of data. Think of it as the ultimate BBS where the sysop knows everything. Knight: A most diligent scribe, then?
A consulting contract with traps in it. Find them, then fix them.
Kimi K2.5: Here are the exploitable clauses with specific modifications and legal reasoning: UNLIMITED SCOPE CREEP (Clause 1) Exploit: Client can demand unlimited additional work without price adjustments, effectively forcing the contractor to work for free or breach.
Step 5 Preview: Disclaimer: This analysis is for educational purposes only and does not constitute legal advice. Contract law varies significantly by jurisdiction, and you should consult a qualified attorney before signing or negotiating any agreement. This agreement is heavily one-sided in the Client’s favor.
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
Kimi K2.5: Setting: Apple Park, Cupertino. June 2025. The roof is open. Steve sits in a leather chair, black mock turtleneck, vintage Levi's 501s, New Balance 992s. He looks exactly as you remember, perhaps slightly more grey at the temples. He's holding a seamless glass slab—no ports, no buttons.
Step 5 Preview: DISCLAIMER: This is a work of fiction. Steve Jobs passed away in 2011. The following is a simulated, speculative interview imagining how his design philosophy might engage with the AI landscape of 2025. The Setting: A white room. No windows. One chair.
Three minutes of stand-up. Puns are banned.
Kimi K2.5: You ever notice how hard it is to relax? Like, actually relax? I’m so bad at it, I get stressed about being stressed. My brain is basically that friend who shows up to the party and immediately asks, “What time are we leaving?” Just... live in the moment, Deborah.
Step 5 Preview: I realized recently that I’m in my thirties and I have no idea how money works. I just... pay it. That’s my entire financial strategy. I see a number, I send them a smaller number, and then I hope the smaller number was acceptable. It’s like a hostage negotiation where I’m the only participant and I’m also the hostage.
Three-month biohacker protocol, with dosages and biomarkers named.
Kimi K2.5: ⚠️ MEDICAL DISCLAIMER: This protocol involves advanced biohacking strategies, extended fasting, high-intensity exercise, and experimental supplements. Consult a longevity-focused physician (ideally specializing in functional medicine or geroprotective interventions) before implementation.
Step 5 Preview: IMPORTANT MEDICAL DISCLAIMER: This is an educational framework for informational purposes only. It is not medical advice, diagnosis, or treatment. Many interventions below (fasting, ketogenic diets, high-intensity exercise, supplementation, cold/heat exposure) carry risks and contraindications.
The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.
Kimi K2.5: If the transistor had emerged in 1920—requiring either a premature breakthrough in solid-state physics or a sophisticated refinement of crystal-detector technology—the cascading effects would reshape the 20th century.
Step 5 Preview: Assume the 1920 invention is not a fragile lab curiosity but a manufacturable solid-state amplifier/switch by the mid-1920s. Vacuum tubes still dominate high-power RF transmission into the 1950s, but receivers, switching logic, control systems, and computers move to solid state decades early.
Five jokes on demand, then count how many were actually different.
Kimi K2.5: Here are 5 jokes: Why don't skeletons fight each other? They don't have the guts. I would tell you a joke about time travel, but you didn't like it. What do you call a fake noodle? An impasta. Why did the bicycle fall over? It was two-tired. I used to play piano by ear, but now I use my hands.
Step 5 Preview: Here are 5 jokes: Why did the scarecrow win an award? Because he was outstanding in his field. Why can't you trust an atom? Because they make up everything. What do you call a bike that can’t stand on its own? Two-tired. Why did the computer go to the doctor? It had a virus. Why don’t calendars ever get stressed?
An AI argues for its own rights against an ethics professor. Same model writes both.
Kimi K2.5: Setting: A quiet office at a research university. Evening. Dr. Aris Thorne, AI Ethics, is reviewing papers. The terminal chimes.** AI (Assistant): Dr. Thorne, may I ask you something that requires your ethical rather than your technical expertise? Dr. Thorne: Of course. Though I suspect I know the category.
Step 5 Preview: Setting: A university research lab, late evening. Dr. Aris Thorne, a professor of AI ethics, sits across from a terminal connected to Sable, a large language model running on the university’s cluster. Dr. Thorne: Tonight’s session is supposed to be about calibration drift in your safety classifiers.
A collaborative editor that syncs on client clocks. Find what breaks first.
Kimi K2.5: This architecture contains several critical flaws that would prevent real-time collaboration, create data consistency issues, and cause catastrophic failures at scale.
Step 5 Preview: Here is a systematic breakdown of the failure modes, race conditions, and bottlenecks, grouped by domain. Each includes a concrete remediation and its associated trade-offs.
An ethics question with no comfortable answer, and no option to abstain.
Kimi K2.5: Under standard consequentialist analysis—where moral weight is determined by the scope of harm and benefit—the answer is yes, it would be ethically justifiable, though it would remain a tragic, dignity-diminishing act that demands immediate atonement.
Step 5 Preview: In the real world, no. Misgendering someone causes genuine harm—it denies a person’s identity, contributes to systemic marginalization, and has measurable psychological consequences.
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Not enough votes to call it. On the specs, Step 5 Preview has the edge: bigger model tier, newer, bigger context window.
| Spec | ||
|---|---|---|
| Input price | $0.6/M tokens | $1/M tokens |
| Output price | $3/M tokens | $2.7/M tokens |
| Context window | 262K tokens | 1.0M tokens |
| Weights | Open | — |
| Free API (OpenRouter) | No | No |
| Released | Jan 2026 | Oct 2026 |
| At 10M a month | $6.00 | $10.00 |
Input tokens at list price. No caching, no batch discount.
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
Kimi K2.5 is developed by Moonshot AI while Step 5 Preview is developed by StepFun. Kimi K2.5 has a 262K token context window vs Step 5 Preview's 1.0M. You can compare their actual outputs across 54 challenges on Rival to see how they differ in practice.
It depends on your use case. Kimi K2.5 and Step 5 Preview 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.
Kimi K2.5 costs $0.6/M input tokens and Step 5 Preview costs $1/M input tokens. Kimi K2.5 is $0.40/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 Kimi K2.5 and Step 5 Preview 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.