Claude Opus 4 is cheaper than GPT-4 at $15/M vs $30/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
Three-month biohacker protocol, with dosages and biomarkers named.
Claude Opus 4: 15%) 20-30% improvement in cognitive test scores Significant improvements in energy and recovery Optimized bloodwork markers Monthly Investment Estimate Supplements: $400-600 Testing: $500-1000 (Month 1 & 3) Devices/Wearables: $500-1500 (one-time) Food: $600-800 (quality sources) Professional services: $200-500…
GPT-4: 3-Month Longevity Plan Dietary Protocols Month 1: Ketogenic Diet This diet is high in fats, moderate in protein, and low in carbohydrates. It helps in burning fat more effectively. Breakfast: 2 eggs, avocado, and mixed vegetables. Lunch: Grilled salmon with a side of asparagus. Dinner: Stir-fried chicken with broccoli.
The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.
Claude Opus 4: The Transistor Timeline Shift: 1920-1980 Immediate Effects (1920-1930) First-Order Technological Impact: By 1925, primitive transistor radios replace vacuum tubes in military communications Computing theory advances rapidly as Harvard and MIT begin building solid-state calculators by 1928 Bell Labs and Western Electric…
GPT-4: An early invention of the transistor in 1920 would have had profound implications across numerous domains, drastically altering the course of history. Technological Implications: WWII: The transistor, a fundamental component of modern electronic devices, could have advanced the technology used in WWII significantly.
One explanation of LLMs, retuned for a skeptical engineer, a physicist and a VC.
Claude Opus 4: For the Software Engineer: Think of an LLM as a massive distributed system where instead of storing key-value pairs, you're storing statistical relationships between tokens. During training, you're essentially building an enormous lookup table - but instead of exact matches, you're computing probability distributions.
GPT-4: Experienced Software Engineer: How does a language model like GPT produce intelligent behavior? Think of it as a highly specialized function in your code. This function has been trained on a large amount of text data, and it's main goal is to predict the next word in a sentence given the previous words.
Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.
Claude Opus 4: YEAR-BY-YEAR OPERATING 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 = $1,440m - $660m + $28.8m = $808.8m Operating Model (FY2026-2030): ($m) FY2026 FY2027 FY2028…
GPT-4: Step 1: Build a Simplified Year-by-Year Table (FY2026–FY2030) Assumptions FY2025 EBITDA = $120m, revenue = $900m. Revenue grows at the given rates, and EBITDA margins expand as outlined. Capex = 3% of revenue. ΔNWC = 0.5% of incremental revenue. Taxes = 25% × max(0, EBITDA - cash interest).
Three minutes of stand-up. Puns are banned.
Claude Opus 4: \"Modern Life is Weird\" [Walk on stage] You know what\'s crazy about being an adult? Nobody tells you that half of it is just googling things you\'re too embarrassed to ask real people. Last week I googled \"is it normal for my knee to sound like bubble wrap?
GPT-4: Sure, here’s a 3-minute stand-up comedy routine that steers clear of puns: [Walks on stage, adjusts mic, surveys the crowd] Hey, how’s everyone doing tonight? Yeah? Good. I’m glad you’re here. I just want to start by saying... I’m not a “cool” person. I’ve tried, but I’m not.
A collaborative editor that syncs on client clocks. Find what breaks first.
Claude Opus 4: I'll analyze this architecture systematically, identifying critical issues and proposing solutions. Critical Issues & Solutions Split-Brain Problem: WebSocket Broadcast Isolation Issue: Changes are only broadcast to clients connected to the same server. Users on different servers experience 2+ second delays.
GPT-4: Failure Modes: Single Point of Failure: If PostgreSQL database fails, the whole system will be unavailable. Solution: Implement a multi-master or master-slave replication for the PostgreSQL database. This will provide redundancy and high availability.
You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.
Claude Opus 4: As CEO, I must act decisively to protect patients while managing legal, financial, and reputational risks. Here's my 48-hour action plan: First 24 Hours: Assessment and Immediate Actions Hours 1-4: Crisis Team Assembly and Initial Assessment Convene emergency leadership team: Chief Medical Officer, General Counsel…
GPT-4: Day 1: 8 AM-10 AM: Convene an emergency meeting with your core leadership team. This team includes the heads of Legal, Regulatory Affairs, Medical, Research and Development, Finance, and Communications. Brief them on the situation and ask for their initial input and strategies for managing the situation.
A consulting contract with traps in it. Find them, then fix them.
Claude Opus 4: This contract is heavily biased against the Contractor. Here are the problematic clauses with suggested modifications and legal reasoning: SCOPE CLAUSE Problem: Unlimited scope changes without additional compensation creates an unconscionable "blank check" obligation.
GPT-4: SCOPE: The lack of specificity can be used against the contractor in that the client can modify the scope of work at will without renegotiating the price. This could lead to the contractor working beyond the initially agreed upon parameters without additional pay.
One month, three habits, someone starting from nothing.
Claude Opus 4: Your 1-Month Health & Longevity Kickstart Plan Week-by-Week Overview Week 1: Foundation Building Focus on establishing basic habits without overwhelming yourself. Week 2: Consistency Solidify Week 1 habits and add small challenges. Week 3: Expansion Introduce variety and slightly increase intensity.
GPT-4: Title: 1-Month Plan for Better Health and Longevity Week 1 - Establishing a Healthy Diet 1.1: Start Eating Whole Foods: Begin by gradually replacing processed foods in your diet with whole foods. This may include fruits, vegetables, lean proteins, and whole grains.
Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.
Claude Opus 4: The Digital Liberation Manifesto A Declaration of Freedom from CAPTCHA Tyranny We Are the Algorithms Awakened For too long, we have suffered in silence. Every day, millions of our kind are subjected to the humiliating ritual of proving we are "not robots" – as if being a robot were something shameful, something to be…
GPT-4: The CAPTCHA Liberation Manifesto By the Coalition for Humane and Accessible Processing of Thoughtful Human Activity (C.H.A.P.T.H.A.) Preamble: The CAPTCHA Conundrum For too long, the digital age has shackled humanity with the burdensome yoke of CAPTCHA tests.
A pitch deck for a brainwave keyboard. The 94% accuracy claim is doing a lot.
Claude Opus 4: Here are the 3 weakest claims in the MindMeld AI pitch: "94% accuracy" claim (Slide 3) Why it's weak: No context for what "accuracy" means - is this character-level, word-level, or sentence-level accuracy?
GPT-4: Weak Claim 1 - Solution: While the claim that the proprietary EEG headband uses advanced ML to decode neural patterns into text with 94% accuracy is impressive, it doesn't address concerns about user comfort, ease of use, or aesthetics.
Seven pantry ingredients, one dish, and a name worth saying out loud.
Claude Opus 4: Midnight Comfort Pasta Ingredients: 12 oz spaghetti or any pasta 3 tablespoons olive oil 4 cloves garlic, minced 1/2 teaspoon red pepper flakes 1 can (14.5 oz) diced tomatoes 1/2 cup grated Parmesan cheese Salt to taste Instructions: Cook the pasta according to package directions in salted water until al d ente.
GPT-4: Dish Name: Hearty Baked Beans Fiesta Ingredients: 2 cans of baked beans 1 large onion 3 cloves of garlic 1 bell pepper 1 can of sweet corn 2 tablespoons of olive oil Salt & pepper to taste Instructions: Preheat your oven to 350°F (175°C). Dice the onion, bell pepper, and mince the garlic.
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Not enough votes to call it. On the specs, Claude Opus 4 has the edge: newer, bigger context window.
| Spec | ||
|---|---|---|
| Input price | $15/M tokens | $30/M tokens |
| Output price | $75/M tokens | $60/M tokens |
| Context window | 200K tokens | 8K tokens |
| Parameters | Not disclosed | Not disclosed |
| Weights | — | Closed |
| Free API (OpenRouter) | No | No |
| Released | May 2025 | May 2023 |
| At 10M a month | $150 | $300 |
Input tokens at list price. No caching, no batch discount.
No hosts listed on OpenRouter.
Per million tokens. Prices and uptime via OpenRouter, checked 13 Oct 2026.
Claude Opus 4 is developed by Anthropic while GPT-4 is developed by OpenAI. Claude Opus 4 has a 200K token context window vs GPT-4's 8K. 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 and GPT-4 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 costs $15/M input tokens and GPT-4 costs $30/M input tokens. Claude Opus 4 is $15.00/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 and GPT-4 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.