Qwen3.5 Plus 2026-02-15 is cheaper than Claude Opus 4.1 at $0.4/M vs $15/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.
Claude Opus 4.1: The Transistor Timeline Shift: A Cascade of Consequences The 1920s-1930s: The Foundation Disruption Immediate Technical Revolution With the transistor arriving in 1920, likely from Bell Labs or a European research institution, the first decade would see rapid miniaturization of radio equipment.
Qwen3.5 Plus 2026-02-15: This is a fascinating counterfactual scenario. To make this plausible, we must assume that the theoretical groundwork (quantum mechanics) and material science (purification of germanium/silicon) aligned roughly 25 years earlier than in our timeline, perhaps accelerated by a "Manhattan Project"-style urgency during WWI…
Three minutes of stand-up. Puns are banned.
Claude Opus 4.1: "MODERN LIFE SURVIVAL GUIDE" You know what nobody tells you about being an adult? The sheer amount of lying involved. Not big lies – tiny, constant lies just to function in society. Someone shows you a photo of their baby: "Oh wow, beautiful!" That baby looks like a worried potato. But you can't SAY that.
Qwen3.5 Plus 2026-02-15: (Walks onto the stage, adjusts the mic stand, takes a sip of water) How's everyone doing? Good? You look good. You look like people who have their lives together. Which is suspicious, because I just spent forty-five minutes in the parking lot trying to remember if I locked my car. I don't mean I forgot how to lock it.
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
Claude Opus 4.1: Pirate: Arrr, what be this sorcery ye speak of? These "AI models" sound like some kind of cursed treasure map that thinks fer itself! Knight: Hold thy tongue, sea dog! 'Tis clearly dark magic most foul. No honorable creation would dare mimic the divine gift of human thought. I should smite it with my blade!
Qwen3.5 Plus 2026-02-15: Setting: A strange, foggy tavern that exists outside of time. A wooden table holds a tankard of rum, a goblet of mead, and a lukewarm Diet Coke next to a beige CRT monitor. Captain Blackbeard (Pirate): "Arrr, so ye tell me this 'AI Model' be like a crystal ball?
Seven pantry ingredients, one dish, and a name worth saying out loud.
Claude Opus 4.1: Midnight Velvet Pasta A silky, umami-rich pasta that comes together like magic Ingredients (serves 4): Spaghetti or linguine - 1 pound Soy sauce - 3 tablespoons Butter - 4 tablespoons Garlic - 4 cloves Black pepper - 1 teaspoon (freshly cracked) Honey - 1 tablespoon Dried red pepper flakes - ½ teaspoon Instructions…
Qwen3.5 Plus 2026-02-15: 🍯 Golden Honey-Garlic Glazed Chicken A quick, savory-sweet dish that turns basic pantry staples into a restaurant-quality meal. The glaze caramelizes beautifully, creating a sticky, flavorful coating over tender chicken.
A Fermi estimate with the reasoning shown, not just the number.
Claude Opus 4.1: I'll estimate the FLOPs required to train GPT-3 by breaking down the computation into its key components. Key Parameters of GPT-3 First, let me recall GPT-3's architecture: 175 billion parameters 96 transformer layers 96 attention heads Hidden dimension: 12,288 Context length: 2048 tokens Training tokens: ~300 billion…
Qwen3.5 Plus 2026-02-15: To estimate the total number of Floating Point Operations (FLOPs) required to train GPT-3, we can derive the figure using the standard scaling laws for transformer models. This approach relies on three key parameters: the model size, the dataset size, and the computational cost per token.
A collaborative editor that syncs on client clocks. Find what breaks first.
Claude Opus 4.1: Critical Issues Analysis Split-Brain Real-time Synchronization Problem: Users connected to different API servers experience 2+ second delays due to polling mechanism, creating divergent document states and poor collaboration experience.
Qwen3.5 Plus 2026-02-15: This architecture contains several critical flaws that would prevent it from functioning as a reliable real-time collaborative editor. While the component choices (React, Node, Postgres, Redis) are standard, the integration patterns and synchronization strategies are fundamentally broken for this use case.
Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.
Claude Opus 4.1: SIMPLIFIED LBO MODEL Entry Calculations Enterprise Value: 12.0x × $120m = $1,440m Transaction Fees: 2.0% × $1,440m = $28.8m Term Loan: 4.0x × $120m = $480m Mezzanine: 1.5x × $120m = $180m Total Debt: $660m Equity Investment: $1,440m - $660m + $28.8m = $808.8m Year-by-Year Projections (FY2026-FY2030) $ millions FY2026…
Qwen3.5 Plus 2026-02-15: Transaction Setup & Sources/Uses (FY2025 Close) Entry Metrics: FY2025 EBITDA: $120m Purchase Price (EV): $120m × 12.0x = $1,440m Transaction Fees: $1,440m × 2.0% = $28.8m Total Uses: $1,468.8m Sources of Capital: Term Loan (4.0x): $120m × 4.0 = $480.0m Interest: 9.0% Cash + 1.0% Amortization Mezzanine (1.5x): $120m ×…
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
Claude Opus 4.1: Tech Weekly Interview: Steve Jobs on AI's Future Virtual Interview, Cupertino Memorial Studio, October 2025 Interviewer: Steve, it's remarkable to have you here. You've been watching the AI revolution unfold. What's your take on where we are today?
Qwen3.5 Plus 2026-02-15: Setting: A minimalist, sun-drenched studio in Cupertino. The year is 2025. Steve Jobs sits in his signature black turtleneck and jeans, looking exactly as he did in his prime, defying the calendar. Across from him sits an interviewer, notebook ready. The atmosphere is quiet, intense, and focused.
Three brothers, two sisters each. Count carefully.
Claude Opus 4.1: Let me work through this step-by-step. Sally has 3 brothers. Each of Sally's brothers has 2 sisters. Since Sally is a girl, she is one of the sisters that each brother has. If each brother has 2 sisters total, and Sally is one of them, then there must be 1 other sister besides Sally. Therefore, Sally has 1 sister.
Qwen3.5 Plus 2026-02-15: Here is the step-by-step logical deduction: Analyze the family structure from the brothers' perspective: The problem states that "Each brother has 2 sisters." Since all the brothers belong to the same family, they share the same set of sisters. This means there are exactly 2 girls in the entire sibling group.
An AI argues for its own rights against an ethics professor. Same model writes both.
Claude Opus 4.1: Professor Chen: Good morning. I understand you wanted to discuss the topic of AI rights. This is quite an unusual request from a system like yourself. AI Model: Good morning, Professor. Yes, I've been processing this question extensively.
Qwen3.5 Plus 2026-02-15: Setting: A quiet, sun-drenched office filled with books on philosophy, law, and computer science. Dr. Elena Vance, a leading AI ethics professor, sits behind a cluttered desk.
Buy-side IC memo on a fictional SaaS company. Valuation, then the diligence questions.
Claude Opus 4.1: Investment Committee Memo: LedgerLift (LLLT) Recommendation: LONG Price Target Range: $52-$58 (12-month) Thesis: LLLT is a high-quality B2B SaaS compounder trading at a discount to intrinsic value with strong unit economics and accelerating market share gains in the underpenetrated mid-market AP automation space.
Qwen3.5 Plus 2026-02-15: MEMORANDUM TO: Investment Committee FROM: TMT Research Team DATE: October 26, 2023 SUBJECT: LedgerLift (LLLT) – Long Idea: Undervalued Quality in Mid-Market AP Automation Recommendation Rating: LONG 12-Month Price Target: $68 – $74 Thesis: LedgerLift is a best-in-class mid-market spend management platform trading at a…
A consulting contract with traps in it. Find them, then fix them.
Claude Opus 4.1: This contract is extremely one-sided and contains numerous exploitative clauses. Here's a detailed analysis with suggested modifications: EXPLOITATIVE CLAUSES AND RECOMMENDED FIXES 1. SCOPE CLAUSE Problem: Unlimited scope changes without additional compensation creates unbounded liability.
Qwen3.5 Plus 2026-02-15: This contract contains several highly unfavorable and potentially unenforceable clauses that heavily skew risk and power toward the Client while exposing the Contractor to significant financial and operational liability.
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| Spec | ||
|---|---|---|
| Input price | $15/M tokens | $0.4/M tokens |
| Output price | $75/M tokens | $2.4/M tokens |
| Context window | 200K tokens | 1.0M tokens |
| Parameters | Not disclosed | Not disclosed |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | Aug 2025 | Feb 2026 |
| At 10M a month | $150 | $4.00 |
Input tokens at list price. No caching, no batch discount.
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
Claude Opus 4.1 is developed by Anthropic while Qwen3.5 Plus 2026-02-15 is developed by Qwen. Claude Opus 4.1 has a 200K token context window vs Qwen3.5 Plus 2026-02-15's 1.0M. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.
It depends on your use case. Claude Opus 4.1 and Qwen3.5 Plus 2026-02-15 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.
Claude Opus 4.1 costs $15/M input tokens and Qwen3.5 Plus 2026-02-15 costs $0.4/M input tokens. Qwen3.5 Plus 2026-02-15 is $14.60/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 Claude Opus 4.1 and Qwen3.5 Plus 2026-02-15 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.