Skip to content
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare Models
  • All Models
  • Image Comparison
  • Audio Comparison
  • Image Generation
  • Best AI For...
  • Arena
  • API Pricing
  • Challenges

Discover

  • SubjectiveBench
  • Default Index
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model Updates
  • Provider Status
  • AI Creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy Policy
  • Terms
  • RSS Feed
  1. Home
  2. /
  3. Compare
  4. /
  5. Laguna S 2.1 (free)vsMercury 2.5 Preview
Updated Aug 2026

Laguna S 2.1 (free)vsMercury 2.5 Preview

Laguna S 2.1 (free) is cheaper than Mercury 2.5 Preview at $0/M vs $0.04/M input tokens.

Laguna S 2.1 (free) and Mercury 2.5 Preview compared across 10 shared prompts
SpecLaguna S 2.1 (free)Mercury 2.5 Preview
Input priceFree$0.04/M tokens
Output priceFree$0.15/M tokens
Context window262K tokens260K tokens
Free API (OpenRouter)Yes (1 provider)No
ReleasedJul 2026Aug 2026
Side by side

Same prompt, both answers

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

Adversarial Contract Review

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

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…
Read the full answer
Mercury 2.5 Preview500 words
Disclaimer: I am an AI assistant and cannot provide legal advice. Consult a qualified attorney before signing any contract. Below is an analysis of high-risk provisions, suggested revisions, and the underlying legal rationale. Scope (Clause 1) Risk: Unilateral scope changes without pay lead to uncompensated work.
Read the full answer

Advanced Longevity Plan (Biohacker)

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

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…
Read the full answer
Mercury 2.5 Preview393 words
Disclaimer: I am an AI assistant, not a medical professional. The following plan is for informational purposes only. Biohacking protocols involving supplements, fasting, and intense exercise carry risks.
Read the full answer

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…

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.
Read the full answer
Mercury 2.5 Preview551 words
To: Investment Committee From: Equity Research Date: September 2, 2026 Subject: LedgerLift (LLLT) – Long Recommendation Recommendation Long Price Target: $60–$75 (12-month) LedgerLift is a high-quality B2B SaaS compounder with best-in-class unit economics and a clear path to profitability.
Read the full answer
Our Verdict
Laguna S 2.1 (free)
Laguna S 2.1 (free)
Mercury 2.5 Preview
Mercury 2.5 Preview

Not enough votes to call it. On the specs, nothing separates them.

Too close to call

Reviewing agent-written code?See a Brief PR report

API pricing

Cost per 1M tokens

Laguna S 2.1 (free)
Input
$0.000
Output
$0.000
Mercury 2.5 Preview
Input
$0.04
Output
$0.15
Where to run it

2 hosts

Laguna S 2.1 (free)1 host
HostInOutContextUptime
PPoolsidefp4$0 in·$0 out·262k·100% up
Mercury 2.5 Preview1 host
HostInOutContextUptime
Inception$0.04 in·$0.15 out·260k·100% up

Per million tokens. Prices and uptime via OpenRouter, checked 23 Sep 2026.

Research

What we learned reading every model

FAQ

Common questions

Laguna S 2.1 (free) is developed by Poolside while Mercury 2.5 Preview is developed by Inception. Laguna S 2.1 (free) has a 262K token context window vs Mercury 2.5 Preview's 260K. You can compare their actual outputs across 10 challenges on Rival to see how they differ in practice.

It depends on your use case. Laguna S 2.1 (free) and Mercury 2.5 Preview 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.

Laguna S 2.1 (free) costs $0/M input tokens and Mercury 2.5 Preview costs $0.04/M input tokens. Laguna S 2.1 (free) is $0.04/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 Laguna S 2.1 (free) and Mercury 2.5 Preview 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.

Keep exploring

More comparisons

Against the newest arrivals

Laguna S 2.1 (free) logoDeepSeek V4 Flash Vision Exp logo
Laguna S 2.1 (free) vs DeepSeek V4 Flash Vision ExpLanded Sep 2026
Mercury 2.5 Preview logoSolar Pro 4 logo
Mercury 2.5 Preview vs Solar Pro 4Landed Sep 2026
Laguna S 2.1 (free) logoHy3 logo
Laguna S 2.1 (free) vs Hy3Landed Sep 2026
Mercury 2.5 Preview logoQwen3.7 Flash logo
Mercury 2.5 Preview vs Qwen3.7 FlashLanded Sep 2026
Laguna S 2.1 (free) logoLing 3.0 Flash logo
Laguna S 2.1 (free) vs Ling 3.0 FlashLanded Sep 2026
Mercury 2.5 Preview logoMuse Glimmer 30B logo
Mercury 2.5 Preview vs Muse Glimmer 30BLanded Sep 2026
Laguna S 2.1 (free) logoGLM 5.3 logo
Laguna S 2.1 (free) vs GLM 5.3Landed Sep 2026
Mercury 2.5 Preview logoTernary Bonsai 2 27B logo
Mercury 2.5 Preview vs Ternary Bonsai 2 27BLanded Sep 2026

Same lab, same size, long tail

Laguna S 2.1 (free) logoLaguna XS 2.1 (free) logo
Laguna S 2.1 (free) vs Laguna XS 2.1 (free)Same lab
Laguna S 2.1 (free) logoOx Alpha logo
Laguna S 2.1 (free) vs Ox AlphaSame size
Mercury 2.5 Preview logoMercury 2.5 logo
Mercury 2.5 Preview vs Mercury 2.5Same lab
Mercury 2.5 Preview logoMercury logo
Mercury 2.5 Preview vs MercurySame lab
Laguna S 2.1 (free) logoGrok 4.3 logo
Laguna S 2.1 (free) vs Grok 4.3Same size
Laguna S 2.1 (free) logoGrok 4.5 logo
Laguna S 2.1 (free) vs Grok 4.5Same size
Laguna S 2.1 (free) logoGrok 4.6 logo
Laguna S 2.1 (free) vs Grok 4.6Same size
Laguna S 2.1 (free) logoGrok 4.7 logo
Laguna S 2.1 (free) vs Grok 4.7Same size

Model pages

Laguna S 2.1 (free) logo
Laguna S 2.1 (free)10 outputs, specs and price
Mercury 2.5 Preview logo
Mercury 2.5 Preview58 outputs, specs and price
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare Models
  • All Models
  • Image Comparison
  • Audio Comparison
  • Image Generation
  • Best AI For...
  • Arena
  • API Pricing
  • Challenges

Discover

  • SubjectiveBench
  • Default Index
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model Updates
  • Provider Status
  • AI Creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy Policy
  • Terms
  • RSS Feed