Claude Opus 5 is cheaper than GPT-4 at $5/M vs $30/M input tokens.
Playable Mario level in one HTML file. The physics is the hard part.
Which answer wins?
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.
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.
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.
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.
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.
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.
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.
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.
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…
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.
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.
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.
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.
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.
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.
GPT-4: Dish Name: Symphony of Scarlet Prawn and Yuzu Conceptual Narrative: This dish is a harmonious interplay of land and sea, with the sweetness of scarlet prawns, a gem of the deep sea, and the refreshing, fragrant citrus notes of yuzu fruit, a treasure from the land.
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.
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.
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.
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.
Not enough votes to call it. On the specs, Claude Opus 5 has the edge: newer, bigger context window.
| Spec | ||
|---|---|---|
| Input price | $5/M tokens | $30/M tokens |
| Output price | $25/M tokens | $60/M tokens |
| Context window | 1.0M tokens | 8K tokens |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | Jul 2026 | May 2023 |
| At 10M a month | $50.00 | $300 |
Input tokens at list price. No caching, no batch discount.
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
Claude Opus 5 is developed by Anthropic while GPT-4 is developed by OpenAI. Claude Opus 5 has a 1.0M token context window vs GPT-4's 8K. You can compare their actual outputs across 26 challenges on Rival to see how they differ in practice.
It depends on your use case. Claude Opus 5 and GPT-4 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 26 challenges so you can judge which fits your needs best.
Claude Opus 5 costs $5/M input tokens and GPT-4 costs $30/M input tokens. Claude Opus 5 is $25.00/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 5 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.