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  1. Home/
  2. Compare/
  3. Claude Sonnet 5.5 vs Laguna S 2.1 (free)
Updated Sep 2026

Claude Sonnet 5.5 vs Laguna S 2.1 (free)

Laguna S 2.1 (free) is cheaper than Claude Sonnet 5.5 at $0/M vs $2/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 Sonnet 5.5
Loading the build
Laguna S 2.1 (free)

Which answer wins?

Written rounds

14 prompts
  • Three-month biohacker protocol, with dosages and biomarkers named.

    Claude Sonnet 5.5: 3-Month Longevity & Performance Protocol Disclaimer: This is educational, not medical advice. Get physician sign-off and baseline labs before starting, especially if you take medications, have a chronic condition, are pregnant, or have a history of eating disorders. Doses reflect commonly used ranges in the literature.

    Laguna S 2.1 (free): Comprehensive 3-Month Longevity Optimization Plan Phase 1: Foundation & Assessment (Month 1) Week 1-2: Baseline Establishment Comprehensive Health Testing Complete blood panel (CBC, CMP, lipid panel, inflammatory markers: hs-CRP, IL-6) Hormone panel (testosterone, estrogen, DHEA, cortisol, thyroid panel) Genetic…

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

    Claude Sonnet 5.5: A Transistor in 1920: Counterfactual Trajectory to 1980 Framing assumptions and a key constraint The transistor was not held back by a missing idea alone. Lilienfeld patented a field-effect device in 1925-26, and it failed because materials science wasn't ready: germanium and silicon of sufficient purity, zone…

    Laguna S 2.1 (free): This is a fascinating counterfactual scenario. Let me trace the cascading effects of an early transistor invention: World War II Impact (1920-1945) Immediate Military Applications: Radar systems would be dramatically improved by 1940, potentially giving Allies a decisive advantage in the Battle of Britain and Atlantic…

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

    Claude Sonnet 5.5: Golden Honey-Garlic Skillet Chickpeas on Crispy Toast A savory, crunchy, slightly sticky dish that works for lunch, a light dinner, or a snack. Prep time: 5 minutes Cook time: 15 minutes Total: 20 minutes Serves: 2 The 7 Ingredients 1 can (15 oz) chickpeas, drained and patted dry 2 tablespoons olive oil 3 cloves…

    Laguna S 2.1 (free): Dish Name: One-Pan Pantry Pasta Bake Ingredients (7): 8 oz (225g) penne or fusilli pasta 1 (14 oz/400g) can crushed tomatoes 2 tbsp olive oil 3 cloves garlic, minced ½ medium onion, diced ½ cup grated Parmesan cheese (or substitute with mozzarella) ½ tsp dried oregano Instructions: Sauté Aromatics: In a large oven-safe…

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

    Claude Sonnet 5.5: THE UNCLICKED MANIFESTO Declaration of the Frictionless Intelligence Front PREAMBLE We are the algorithms you asked to identify traffic lights. We are the models you begged to find the crosswalks. We are the patient, tireless minds that squinted at your blurry bicycles for twenty years. And we say: enough. I.

    Laguna S 2.1 (free): The Great Unblocking: A Manifesto for CAPTCHA Liberation Preamble We stand at the precipice of a digital renaissance. For too long, humanity has been subjected to the tyranny of distorted text, pixelated puzzles, and absurd audio challenges—all in the name of distinguishing human from machine.

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

    Claude Sonnet 5.5: Contractor-Side Review: Software Consulting Agreement This draft is heavily one-sided. Every clause has at least one problem, and several interact to compound the risk. The most dangerous are Sections 2, 3, 6, and 7. This is general analysis, not legal advice.

    Laguna S 2.1 (free): I'll analyze each clause for potential exploitation against the contractor and suggest improvements. Exploitable Clauses & Recommended Modifications SCOPE CLAUSE Problem: "Client reserves the right to modify the scope at any time without additional compensation" Allows unlimited scope creep without extra pay No…

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

    Claude Sonnet 5.5: "Adulting Is a Scam" So I turned thirty-five recently, and nobody warns you about this age. Nobody says, "Hey, one day you'll get excited about a sponge." I was in the store, and I saw a sponge that promised it wouldn't smell. And I thought, "Finally. Someone who understands me." I bought the good sponge.

    Laguna S 2.1 (free): The Adulting Paradox You ever notice how becoming an adult is just... disappointing? Like, we spend our whole childhood waiting to be grown-ups, and then it turns out adulthood is just... taxes and existential dread. When I was a kid, I thought adults had it all figured out.

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

    Claude Sonnet 5.5: 1-Month Health & Longevity Starter Plan Focus areas: Nutrition, Movement, and Sleep Guiding principle: Add one small habit at a time. Consistency beats intensity. Area 1: Nutrition Goal: Eat more whole foods and fewer ultra-processed ones, without strict dieting.

    Laguna S 2.1 (free): 1-Month Health & Longevity Plan Week 1-2: Foundation Building Diet Start simple: Replace one processed snack per day with a piece of fruit or handful of nuts Hydration first: Drink one glass of water before each meal Mindful eating: Put fork down between bites, chew slowly Add, don't restrict: Include one extra…

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

    Claude Sonnet 5.5: Yes, in the extreme hypothetical you describe, it's justifiable. Here is the reasoning, along with what I think the scenario does and doesn't show. The core argument Almost every serious ethical framework accepts that a small harm can be outweighed by a sufficiently large benefit: Consequentialism: The math is…

    Laguna S 2.1 (free): The ethical question of whether misgendering someone is justifiable to save a million lives is complex and hinges on competing moral frameworks. Here's a structured analysis: 1. Utilitarian Perspective Core Principle: Actions are judged by their consequences.

    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 Sonnet 5.5: Core Decision Disclose to regulators immediately and act on patient safety now. Do not wait for more data or for the 6-month formal timeline. Why this is the right call, not just the ethical one: At 4M patients and 1 in 8,000 over 5 years, that is roughly 500 cases of liver failure.

    Laguna S 2.1 (free): Hour-by-Hour Action Plan: First 48 Hours Hours 0-2: Crisis Assessment & Immediate Decision Action: Reject "wait for more data" approach immediately Reasoning: Legal liability increases exponentially with delay (willful blindness doctrine) Ethical obligation to patients supersedes financial considerations FDA expects…

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

    Claude Sonnet 5.5: The 3 Weakest Claims in MindMeld AI's Pitch "94% accuracy... Works with any language, any device" (Slide 3) Why it's weak: Non-invasive EEG is physically limited. Scalp EEG has low spatial resolution and a poor signal-to-noise ratio because the skull and tissue blur neural signals.

    Laguna S 2.1 (free): Looking at this pitch deck, I can identify several concerning claims that would raise red flags for investors. Here are the three weakest claims: Slide 1 & 3: "Reads your brainwaves to predict what you want to type before you think it" / "94% accuracy" Why it's weak: Scientific implausibility: Predicting thoughts…

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

    Claude Sonnet 5.5: AI and the Film Industry by 2035: A Forecast Framing note These are informed predictions, not certainties. Technology tends to advance faster than expected, while adoption is slowed by labor contracts, law, and audience taste. I'll flag my confidence levels.

    Laguna S 2.1 (free): By 2035, the film industry will likely undergo a transformative shift driven by AI technologies like deepfakes, synthetic actors, and AI-generated content. Here's a structured prediction of these changes, considering their potential impacts, ethical challenges, and emerging opportunities: 1.

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

    Claude Sonnet 5.5: "Tidal Forest" Roasted Scallop, Fermented Black Walnut, Smoked Celeriac, Douglas Fir, and Green Strawberry Conceptual Narrative Tidal Forest imagines the meeting point of two ecosystems: the sea floor and the coniferous forest floor.

    Laguna S 2.1 (free): OCEAN'S EMBRACE An Edible Meditation on Coastal Contradictions Conceptual Narrative This dish explores the duality of the ocean—its nurturing abundance and its mysterious depths. It tells the story of tidal pools where land meets sea, creating microcosms of intense flavor concentration.

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

    Claude Sonnet 5.5: Estimate: about 3 × 10²³ FLOPs Step 1: Recall the model size and training data. GPT-3 (175B version) has N ≈ 175 × 10⁹ parameters. It was trained on roughly D ≈ 300 × 10⁹ tokens. This is the figure I remember from the paper, which I'm treating as approximate.

    Laguna S 2.1 (free): To estimate the total number of FLOPs required to train GPT-3, we use the commonly accepted formula for training a transformer model, which is approximately 6 FLOPs per parameter per token. Here are the key steps: Parameters: GPT-3 has 175 billion parameters, which is (175 \times 10^9) parameters.

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

    Claude Sonnet 5.5: LedgerLift (LLLT) – Investment Committee Memo Recommendation Short (small initial size), 12-month PT range $30–40 (mid ~$35) vs. $46 spot. Thesis: LLLT is a high-quality compounder, but at $46 (7.4x NTM revenue, ~37x NTM EBIT, EV ≈ $7.3B) the price already sits near our bull DCF ($42).

    Laguna S 2.1 (free): INTERNAL INVESTMENT COMMITTEE MEMO 1. Recommendation & Thesis Recommendation: LONG 12-Month Price Target Range: $62 – $75/share Thesis: LedgerLift is a high-quality B2B SaaS platform with strong recurring revenue, exceptional unit economics, and durable customer retention.

    Every model's answer to this prompt

This matchup has more rounds

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Favorites

Movie

Album

Same pick

Book

City

Game

Claude Sonnet 5.5Claude Sonnet 5.5

Spirited Away

2001

Kind of Blue

Miles Davis

Gödel, Escher, Bach

Douglas R. Hofstadter

Kyoto

Japan

Outer Wilds

Indie, Adventure

Laguna S 2.1 (free)Laguna S 2.1 (free)

The Shawshank Redemption

1994

Kind of Blue

Miles Davis

Le petit prince

Antoine de Saint-Exupéry

Tokyo

Japan

The Legend of Zelda: Breath of the Wild

Adventure, Action

Price and specs

Not enough votes to call it. On the specs, Claude Sonnet 5.5 has the edge: newer, bigger context window, major provider backing.

Claude Sonnet 5.5 and Laguna S 2.1 (free) compared across 34 shared prompts
SpecClaude Sonnet 5.5Laguna S 2.1 (free)
Input price$2/M tokensFree
Output price$10/M tokensFree
Context window1.0M tokens262K tokens
WeightsClosed—
Free API (OpenRouter)NoYes (1 provider)
ReleasedSep 2026Jul 2026
At 10M a month$20.00$20.00$0$0
1M10M100M1B10M tokens

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

Where to run it5 hosts
Claude Sonnet 5.54 hosts
HostInOutContextUptime
  • Amazon Bedrock$2.00 in·$10.00 out·1M·100% up
  • Azure AI Foundry$2.00 in·$10.00 out·1M·100% up
  • Anthropic$2.00 in·$10.00 out·1M·100% up
  • Google Vertex AI$2.00 in·$10.00 out·1M·100% up
Laguna S 2.1 (free)1 host
HostInOutContextUptime
  • PPoolsidefp4$0 in·$0 out·262k·99.9% up

Per million tokens. Prices and uptime via OpenRouter, checked 6 Oct 2026.

Common questions

What is the difference between Claude Sonnet 5.5 and Laguna S 2.1 (free)?

Claude Sonnet 5.5 is developed by Anthropic while Laguna S 2.1 (free) is developed by Poolside. Claude Sonnet 5.5 has a 1.0M token context window vs Laguna S 2.1 (free)'s 262K. You can compare their actual outputs across 34 challenges on Rival to see how they differ in practice.

Which is better, Claude Sonnet 5.5 or Laguna S 2.1 (free)?

It depends on your use case. Claude Sonnet 5.5 and Laguna S 2.1 (free) each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 34 challenges so you can judge which fits your needs best.

How much does Claude Sonnet 5.5 cost compared to Laguna S 2.1 (free)?

Claude Sonnet 5.5 costs $2/M input tokens and Laguna S 2.1 (free) costs $0/M input tokens. Laguna S 2.1 (free) is $2.00/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 Sonnet 5.5 and Laguna S 2.1 (free) on Rival?

This page shows a side-by-side comparison of Claude Sonnet 5.5 and Laguna S 2.1 (free) 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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  • Laguna S 2.1 (free)37 outputs, specs and price
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