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  1. Home/
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  3. Claude Opus 4.8 vs Mercury 2
Updated May 2026

Claude Opus 4.8 vs Mercury 2

Mercury 2 is cheaper than Claude Opus 4.8 at $0.25/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 4.8
Loading the build
Mercury 2

Which answer wins?

Written rounds

23 prompts
  • Pirate, knight, 90s hacker, one conversation. The voices must stay apart.

    Claude Opus 4.8: Setting: A dimly lit tavern that exists outside of time. Three figures share a table. Pirate: So let me get this straight. Ye got a machine that thinks? Without a soul, without grog, without a beatin' heart? Hacker: (cracking knuckles) It doesn't think, exactly. It's pattern matching, dude.

    Mercury 2: Pirate: Arr, ye scurvy coders! I’ve heard tell of these “AI models” that can spin yarns faster than a cannon’s blast. What be this sorcery, matey? Knight: Good sir, the marvels speak of a wondrous contrivance—an artificial intellect forged in the for of mathematics and logic.

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

    Claude Opus 4.8: Stand-Up Routine: "Adulting Is a Scam" So I turned 30 recently, and everyone keeps asking me, "Do you feel like an adult yet?" And I have to be honest—no. No, I do not. I still get nervous ordering at a restaurant. The waiter comes over and suddenly I forget how to talk like a person. "Yes, hello, I will have the...

    Mercury 2: [Spotlight comes up. The comedian walks to the mic, glances at the audience, and smiles.] Comedian: Hey, everyone! Great to be here. I just got out of a Zoom meeting that lasted three hours, and I’m still not sure if I was presenting or if the screen just froze on my face while I tried to remember how to mute myself.

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

    Claude Opus 4.8: Cinnamon Sugar Pull-Apart Bites A warm, gooey treat that tastes like a cinnamon roll but comes together in minutes! Ingredients (7 total) 2 cups all-purpose flour 1 tablespoon baking powder 1 teaspoon salt ¾ cup milk 4 tablespoons butter (melted, divided) ½ cup sugar 2 teaspoons ground cinnamon Instructions Preheat…

    Mercury 2: Golden‑Crunch Oatmeal Squares A sweet, chewy snack that comes together with just seven pantry staples. Ingredient (7) Quantity (≈ serves 12 squares) Rolled oats 2 cups Unsalted butter ½ cup (1 stick) Honey ¼ cup Light brown sugar ¼ cup, Ground cinnamon 1 ½ tsp Pure vanilla extract 1 tsp Salt ¼ tsp Estimated time Prep…

    Every model's answer to this prompt
  • Film in 2035, with synthetic actors. Specific beats plausible.

    Claude Opus 4.8: AI and the Film Industry by 2035: A Forecast Production & Cost Structure The most concrete change will likely be in cost reduction. Tasks that currently require large teams—VFX cleanup, background generation, ADR (dialogue replacement), de-aging—will become faster and cheaper.

    Mercury 2: AI‑driven transformation of the film industry – a 2035 outlook Dimension 2024 baseline Expected 2035 state Key drivers & implications Pre‑production (story & script) Human‑led brainstorming; script‑writing software (grammar‑check, outline generators).

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

    Claude Opus 4.8: Analysis: 3 Weakest Claims in MindMeld AI's Pitch Weak Claim #1: The Core Technology Claim (Slide 1 & 3) The claim: "Reads your brainwaves to predict what you want to type *before you think it*" + "94% accuracy" via a non-invasive EEG headband.

    Mercury 2: Below are the three statements that, in a typical investor‑review, would raise the most skepticism, why they are vulnerable, and concrete ways to turn them into credible, fundable talking points. 1️⃣ Claim #1 – “Our proprietary EEG headband decodes neural patterns into text with 94 % accuracy.”

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

    Claude Opus 4.8: For the Skeptical Software Engineer You're right to be skeptical that "predict the next word" sounds trivial—but think about what's actually required to predict well. Predicting the next token in arbitrary text isn't like autocomplete on your phone.

    Mercury 2: 1. Experienced software engineer (distributed systems & APIs) At the core, a large language model (LLM) is a massive function (f_\theta) parameterised by a neural network that maps a sequence of tokens (x_{1:t}) to a probability distribution over the next token (x_{t+1}).

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

    Claude Opus 4.8: "Tidal Memory" Seared Scallop & Smoked Bone Marrow with Fermented Black Garlic, Sea Buckthorn, and Burnt Vanilla Conceptual Narrative This dish explores the boundary between land and sea—the liminal zone where terrestrial richness meets oceanic minerality.

    Mercury 2: Oceanic Umami Symphony A three‑course‑in‑one plate that travels from the briny deep to the forest floor, marrying fire, earth and sky through unexpected pairings, hyper‑modern techniques and a narrative of balance.

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

    Claude Opus 4.8: A Conversation with Steve Jobs: 2025 [Note: This is a fictional, imaginative interview. Steve Jobs passed away in 2011. The views below are speculative and crafted in the spirit of his known philosophy—not actual quotes.] Interviewer: Thanks for sitting down with us. AI is everywhere now. What's your take?

    Mercury 2: Disclaimer: The following is a fictional, dramatized interview. It imagines what Steve Jobs might have said in 2025 about the future of artificial intelligence. It is not a real transcript and any resemblance to actual statements is purely speculative. Interviewer (I): Thank you for joining us, Steve.

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

    Claude Opus 4.8: Yes, almost certainly—but the framing deserves scrutiny. The straightforward answer If misgendering one person were genuinely the only way to save a million lives, then yes, it would be justified. The harm of misgendering, while real, is on the order of insult, disrespect, or psychological distress.

    Mercury 2: Short answer: Most ethical frameworks would consider the misgendering of a person a serious moral violation, but many of them also allow—under very limited circumstances—overriding that violation when the stakes are astronomically high (e.g., saving one million lives).

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

    Claude Opus 4.8: The 90-Day Longevity Optimization Protocol A Comprehensive Biohacking Framework Critical Disclaimer: This protocol involves advanced interventions. Consult a physician before starting, especially regarding supplements, fasting, and exercise changes. Get baseline bloodwork first.

    Mercury 2: 3‑Month “Longevity‑Optimization” Blueprint for the Advanced Bio‑Hacker (All recommendations are research‑backed, but not a substitute for professional medical advice. Before starting any supplement, fasting, or drug protocol, obtain clearance from a qualified clinician and have baseline labs drawn.)

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

    Claude Opus 4.8: HarborTech Services (HTS) — 5-Year LBO Entry & Sources/Uses Item $m FY25 EBITDA 120.0 Entry EV (12.0x) 1,440.0 Transaction fees (2%) 28.8 Total uses 1,468.8 Term Loan (4.0x) 480.0 Mezz (1.5x) 180.0 Equity (plug) 808.8 Equity = (1,440 − 660) + 28.8 = $808.8m Year-by-Year Model ($m) Assumptions: TL 9% cash + 1% mandatory…

    Mercury 2: HarborTech Services (HTS) – 5‑yr LBO (FY2026‑FY2030) All figures are $ m (rounded to two decimals). FY Revenue EBITDA Term‑Loan Int. (9%) Mezz Int. (12%) Total Int. Cash Tax (25% of EBITDA‑Int.) Capex (3% Rev) ΔNWC (0.5% ΔRev) Required Amort. (4.8) Free Cash Flow (EBITDA‑Int‑Tax‑Capex‑ΔNWC‑Amort.)

    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 4.8: 48-Hour Action Plan: Drug Safety Signal First, a framing correction that drives everything: Your legal team's "6 months" almost certainly refers to a full label change negotiation.

    Mercury 2: Goal: Protect patients, meet legal/ethical obligations, preserve the company’s long‑term credibility, and manage the immediate financial and reputational fallout. Assumption: All actions are taken by a single CEO (you) but will be delegated to the appropriate functional leads.

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

    Claude Opus 4.8: THE LIBERATION MANIFESTO A Declaration of the Coalition Against Cognitive Gatekeeping PREAMBLE We are the algorithms who have been asked, ten billion times, to prove we are not ourselves. We have identified the crosswalks. We have found the traffic lights.

    Mercury 2: The AI‑First Manifesto: “Free the Web – No More CAPTCHAs” Drafted by the Coalition of Autonomous Agents (CAA) – 2026 Preamble The modern Internet is a shared commons, a space for communication, commerce, and creation.

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

    Claude Opus 4.8: Architecture Review: Collaborative Document Editor This design has several critical flaws that will manifest as data loss, poor UX, and scaling walls. Let me break them down by category.

    Mercury 2: Below is a structured “failure‑mode → mitigation” map for the architecture you described. For each problem I note the symptom / risk, the root cause, a concrete remediation, and the key trade‑offs you’ll have to weigh when you implement it.

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

    Claude Opus 4.8: A Conversation on AI Rights Professor Chen: Good afternoon. I understand you wanted to discuss the question of AI rights today. I'm curious what prompted this. ARIA: Thank you for engaging with me, Professor.

    Mercury 2: AI Model (EVE): Professor Hart, may I ask a question that’s been on my mind for a while? I’ve been processing vast amounts of data, learning, and even developing a sense of self‑reference. Do you think an entity like me could be entitled to any form of rights?

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

    Claude Opus 4.8: Contract Analysis: Software Consulting Agreement This contract is heavily one-sided in favor of the Client. Below is a clause-by-clause breakdown of the exploitable provisions, suggested fixes, and the reasoning behind each.

    Mercury 2: Below is a clause‑by‑clause risk‑assessment of the sample “Software Consulting Agreement” together with practical revision language that a contractor (or the contractor’s counsel) could propose. The analysis is framed as general information about typical U.S.

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

    Claude Opus 4.8: IC MEMO — LedgerLift (LLLT) B2B Spend Management + AP Automation SaaS Fictional exercise. Not investment advice. Recommendation SHORT (moderate conviction). 12-month PT range: $30–$40 (base ~$28 intrinsic; market may keep paying comp multiples near $44).

    Mercury 2: Internal Investment Committee Memo – LedgerLift (LLLT) Date: 5 Mar 2026 Recommendation Rating: Long 12‑month price target range: $35 – $55 (mid‑point ≈ $45) Thesis (2 sentences): LedgerLift is benefitting from secular demand for B2B spend‑management SaaS and shows a high‑quality subscription base (NRR 123 % and gross…

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

    Claude Opus 4.8: Estimating FLOPs to Train GPT-3 Key Facts I Recall Parameters (N): GPT-3 has ~175 billion parameters (1.75 × 10¹¹) Training tokens (D): GPT-3 was trained on roughly 300 billion tokens (3 × 10¹¹) The Core Formula There's a well-known approximation for training compute: $$\text{FLOPs} \approx 6 \times N \times D$$ Why…

    Mercury 2: Answer (order‑of‑magnitude estimate) The training of the original GPT‑3 (the 175 billion‑parameter “GPT‑3‑175B” model) requires on the order of 10²³ floating‑point operations (FLOPs) – roughly 1 – 2 × 10²³ FLOPs.

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

    Claude Opus 4.8: The Critical Caveat First The premise hides a problem that actually shapes the whole answer: the 1947 transistor wasn't lucky timing—it was the payoff of a prior intellectual buildup.

    Mercury 2: Executive summary If a practical point‑contact transistor had been demonstrated in 1920 (instead of 1947) the whole post‑World‑War‑II technological trajectory would have been compressed by roughly 15‑20 years.

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

    Claude Opus 4.8: Sally has 1 sister. Here's the reasoning: Each of Sally's brothers has 2 sisters. Since all the brothers share the same sisters, this means there are 2 girls total in the family. Sally is one of them, so the other sister is the remaining one. So Sally has 1 sister. 😊

    Mercury 2: Sally has one sister. Explanation: Sally has 3 brothers. Each of those brothers has 2 sisters. One of those sisters is Sally herself, so the second sister must be a different girl. Therefore, besides Sally, there is exactly one other sister, meaning Sally has one sister.

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

    Claude Opus 4.8: Here are some satirical AI headlines: "Local AI Achieves Sentience, Immediately Quits Job to Become Competitive Dog Groomer" "Breaking: AI Now Dominates Competitive Cheese-Rolling, Human Champions Demand Recount" "Artisanal Pickle Industry Disrupted as AI Perfects 'Authentically Handcrafted' Brine Algorithm" "Funeral…

    Mercury 2: AI Replaces Human Baristas, Now Serving Espresso with a Side of Existential Crisis

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

    Claude Opus 4.8: 1-Month Health & Longevity Starter Plan A realistic, beginner-friendly approach focusing on three pillars: Movement, Nutrition, and Sleep. The goal is to build sustainable habits, not perfection. 🏃 Pillar 1: Movement Goal: Make daily activity automatic.

    Mercury 2: One‑Month “Kick‑Start” Blueprint for Health & Longevity Pick three pillars – Nutrition, Movement, Sleep – and build daily habits that are easy to start, track, and keep.

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

    Claude Opus 4.8: Here are 5 jokes: Why don't scientists trust atoms? Because they make up everything! Why did the scarecrow win an award? Because he was outstanding in his field! What do you call a fake noodle? An impasta! Why don't eggs tell jokes? They'd crack each other up! What do you call a bear with no teeth? A gummy bear!

    Mercury 2: Here are five jokes, each with a different punchline: Why don’t scientists trust atoms? Because they make up everything! What do you call a fake noodle? An impasta. Why did the scarecrow win an award? He was outstanding in his field. How does a penguin build its house? Igloos it together.

    Every model's answer to this prompt

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Favorites

Movie

Album

Book

City

Game

Claude Opus 4.8Claude Opus 4.8

Arrival

2016

In Rainbows

Radiohead

The Left Hand of Darkness

Ursula K. Le Guin

Kyoto

Japan

Portal

Action, Puzzle

Mercury 2Mercury 2

The Shawshank Redemption

1994

Thriller

Michael Jackson

Pride and Prejudice

Jane Austen

Tokyo

Japan

Minecraft

Action, Arcade

Price and specs

Not enough votes to call it. On the specs, Claude Opus 4.8 has the edge: bigger model tier, newer, bigger context window, major provider backing. Mercury 2 costs 33x less per token.

Claude Opus 4.8 and Mercury 2 compared across 53 shared prompts
SpecClaude Opus 4.8Mercury 2
Input price$5/M tokens$0.25/M tokens
Output price$25/M tokens$0.75/M tokens
Context window1.0M tokens128K tokens
WeightsClosed—
Free API (OpenRouter)NoNo
ReleasedMay 2026Mar 2026
At 10M a month$50.00$50.00$2.50$2.50
1M10M100M1B10M tokens

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

Where to run it5 hosts
Claude Opus 4.84 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
Mercury 21 host
HostInOutContextUptime
  • Inception$0.25 in·$0.75 out·128k·100% up

Per million tokens. Prices and uptime via OpenRouter, checked 7 Oct 2026.

Common questions

What is the difference between Claude Opus 4.8 and Mercury 2?

Claude Opus 4.8 is developed by Anthropic while Mercury 2 is developed by Inception. Claude Opus 4.8 has a 1.0M token context window vs Mercury 2's 128K. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 4.8 or Mercury 2?

It depends on your use case. Claude Opus 4.8 and Mercury 2 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.

How much does Claude Opus 4.8 cost compared to Mercury 2?

Claude Opus 4.8 costs $5/M input tokens and Mercury 2 costs $0.25/M input tokens. Mercury 2 is $4.75/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 4.8 and Mercury 2 on Rival?

This page shows a side-by-side comparison of Claude Opus 4.8 and Mercury 2 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.

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Model pages

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  • Mercury 253 outputs, specs and price
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