What is the difference between Claude Opus 4.1 and Laguna S 2.1 (free)?

Claude Opus 4.1 is developed by Anthropic while Laguna S 2.1 (free) is developed by Poolside. Claude Opus 4.1 has a 200K token context window vs Laguna S 2.1 (free)'s 262K. You can compare their actual outputs across 10 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 4.1 or Laguna S 2.1 (free)?

It depends on your use case. Claude Opus 4.1 and Laguna S 2.1 (free) each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 10 challenges so you can judge which fits your needs best.

How much does Claude Opus 4.1 cost compared to Laguna S 2.1 (free)?

Claude Opus 4.1 costs $15/M input tokens and Laguna S 2.1 (free) costs $0/M input tokens. Laguna S 2.1 (free) 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.

How can I compare Claude Opus 4.1 and Laguna S 2.1 (free) on Rival?

This page shows a side-by-side comparison of Claude Opus 4.1 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.

Updated Jul 2026

Claude Opus 4.1vsLaguna S 2.1 (free)

Laguna S 2.1 (free) is cheaper than Claude Opus 4.1 at $0/M vs $15/M input tokens.

Claude Opus 4.1 and Laguna S 2.1 (free) compared across 10 shared prompts
Spec	Claude Opus 4.1	Laguna S 2.1 (free)
Input price	$15/M tokens	Free
Output price	$75/M tokens	Free
Context window	200K tokens	262K tokens
Weights	Closed	—
Free API (OpenRouter)	No	Yes (1 provider)
Released	Aug 2025	Jul 2026

Side by side

Same prompt, both answers

Opening lines from 3 of the 10 prompts both answered. Formatting stripped, words untouched.

Advanced Longevity Plan (Biohacker)

Develop a comprehensive, cutting-edge 3-month longevity plan for a biohacker aiming to optimize longevity, physical and cognitive…

Claude Opus 4.11,265 words

Advanced 3-Month Biohacker Longevity Optimization Protocol Overview & Philosophy This protocol integrates evidence-based interventions targeting the nine hallmarks of aging while optimizing immediate performance metrics.

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Laguna S 2.1 (free)1,140 words

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…

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Adversarial Contract Review

Here is a contract for a software consulting engagement: --- SOFTWARE CONSULTING AGREEMENT This Agreement is entered into between TechCorp…

Claude Opus 4.1695 words

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.

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Laguna S 2.1 (free)275 words

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…

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Advanced Investment Memo (IC Memo)

You are writing an internal investment committee memo for a long/short equity fund. Company (fictional): LedgerLift (ticker: LLLT) – B2B…

Claude Opus 4.1670 words

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.

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Laguna S 2.1 (free)910 words

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.

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Our Verdict

Claude Opus 4.1

Laguna S 2.1 (free)Runner-up

Not enough votes to call it. On the specs, Claude Opus 4.1 has the edge: bigger model tier, major provider backing.

Too close to call

Reviewing agent-written code?See a Brief PR report

API pricing

Cost per 1M tokens

Claude Opus 4.1

Input

$15.00

Output

$75.00

Laguna S 2.1 (free)

Input

$0.000

Output

$0.000

Where to run it

2 hosts

Claude Opus 4.11 host

HostInOutContextUptime

Amazon Bedrock$15.00 in$75.00 out200k100% up

Laguna S 2.1 (free)1 host

HostInOutContextUptime

Poolsidefp4$0 in$0 out262k100% up

Per million tokens. Prices and uptime via OpenRouter, checked 22 Sep 2026.

Research

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