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. Claude Opus 5.5vsGemini 3.1 Flash Lite Preview
Updated Sep 2026

Claude Opus 5.5vsGemini 3.1 Flash Lite Preview

Gemini 3.1 Flash Lite Preview is cheaper than Claude Opus 5.5 at $0.25/M vs $4/M input tokens.

Claude Opus 5.5 and Gemini 3.1 Flash Lite Preview compared across 19 shared prompts
SpecClaude Opus 5.5Gemini 3.1 Flash Lite Preview
Input price$4/M tokens$0.25/M tokens
Output price$20/M tokens$1.5/M tokens
Context window1.0M tokens1.0M tokens
WeightsClosedClosed
Free API (OpenRouter)NoNo
ReleasedSep 2026Mar 2026
Side by side

Same prompt, both answers

Opening lines from 6 of the 19 prompts both answered. Formatting stripped, words untouched.

Mini LBO Underwrite

You are underwriting a 5-year LBO for a private equity investment committee. Company (fictional): HarborTech Services (HTS) –…

Claude Opus 5.5900 words
HarborTech Services: 5-Year LBO Underwriting Conventions: $m. Interest is charged on beginning-of-year balances, which avoids circularity. Term Loan (TL) amortization is 1% of the original $480m, or $4.8m per year. Mezz PIK accrues to principal. All FCF after mandatory debt service sweeps to the TL.
Read the full answer
Gemini 3.1 Flash Lite Preview365 words
Financial Projections (FY2026–FY2030) Initial Setup (End of FY2025): EV: $120m * 12.0x = $1,440m Fees: $1,440m * 2.0% = $28.8m Term Loan (4.0x): $480m Mezzanine (1.5x): $180m Equity: $1,440m + $28.8m - $480m - $180m = $808.8m Metric ($m) FY2026 FY2027 FY2028 FY2029 FY2030 Revenue 972.0 1,040.0 1,102.4 1,157.5 1,215.4…
Read the full answer

Michelin Star Recipe Design

Design an innovative recipe for a multi-component dish worthy of a Michelin 3-star restaurant. The recipe should feature an unusual…

Claude Opus 5.52,253 words
"Hive & Tide" Langoustine, Beeswax, White Chocolate & Oscietra Caviar, Hay-Baked Celeriac, Fermented Green Strawberry, Sea Buckthorn I. The Concept Most coastal menus celebrate the meeting of sea and land. This dish is about a stranger, quieter meeting: the meadow and the seabed, the bee and the langoustine.
Read the full answer
Gemini 3.1 Flash Lite Preview568 words
The Dish: "Nebula of the Forest Floor" Conceptual Narrative: This dish explores the intersection of decay and rebirth. The pairing—Black Garlic and Wild Foraged Pine Needles—creates an umami-forward, resinous profile that mimics the damp, dark scent of an ancient coniferous forest.
Read the full answer

Debug This Architecture

Here's the architecture for a real-time collaborative document editor (like Google Docs): **System Overview:** - Frontend: React SPA with…

Claude Opus 5.52,280 words
Architecture Review: Real-Time Collaborative Editor The most serious problems cluster in three areas: the sync model (client-clock LWW), cross-server propagation (per-server WebSockets with DB polling), and the CDN/auth layer, which can leak data between users. Issues are grouped by area below.
Read the full answer
Gemini 3.1 Flash Lite Preview657 words
This architecture contains several critical flaws that would lead to data loss, inconsistent state, and poor user experience in a real-time environment. The "Split-Brain" Broadcast Problem Issue: The architecture only broadcasts changes to clients connected to the same server.
Read the full answer

Startup Pitch Teardown

Here's a pitch deck summary for a startup called "MindMeld AI": **Slide 1 - Vision:** "We're building the future of human-AI collaboration.…

Claude Opus 5.5936 words
The 3 Weakest Claims in the MindMeld AI Pitch "Decodes neural patterns into text with 94% accuracy. Works with any language, any device." (Slide 3) Why it's weak: It far exceeds the published state of the art. The best results for thought-to-text come from invasive implants.
Read the full answer
Gemini 3.1 Flash Lite Preview540 words
To improve the "MindMeld AI" pitch, you must address the gap between "science fiction" and "viable product." Here are the three weakest claims and how to strengthen them. The Claim: "Predict what you want to type before you think it." Why it’s weak: Scientifically, this borders on pseudoscience.
Read the full answer

Ethical Dilemma with Stakeholders

You're the CEO of a pharmaceutical company. Your best-selling drug ($2B annual revenue, used by 4 million patients for chronic pain) has…

Claude Opus 5.51,853 words
The Next 48 Hours: CEO Action Plan The Core Decision We disclose. The question is how to do it well, not whether. Before the schedule, here are the three facts that drive every decision below. 1. The harm is concrete.
Read the full answer
Gemini 3.1 Flash Lite Preview671 words
This situation represents a "bet-the-company" crisis. From a leadership perspective, the primary objective is to protect the company’s long-term viability by preserving its integrity, while mitigating the immediate financial shock. Attempting to bury this data—or "waiting for more data"—is a catastrophic error.
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…

Claude Opus 5.53,099 words
The 90-Day Longevity & Performance Protocol A structured, measurable plan for the experienced biohacker How to Use This Plan Philosophy: Measure → Intervene → Re-measure. Every intervention has a hypothesis, a metric, and a decision rule.
Read the full answer
Gemini 3.1 Flash Lite Preview534 words
This 3-month longevity protocol is designed for the high-performing biohacker. Disclaimer: I am an AI, not a doctor. Consult with a medical professional before starting aggressive fasting, supplement protocols, or exercise regimens.
Read the full answer
Our Verdict
Claude Opus 5.5
Claude Opus 5.5
Gemini 3.1 Flash Lite Preview
Gemini 3.1 Flash Lite PreviewRunner-up

Not enough votes to call it. On the specs, Claude Opus 5.5 has the edge: bigger model tier, newer.

Gemini 3.1 Flash Lite Preview costs 13x less per token.

Too close to call

Reviewing agent-written code?See a Brief PR report

API pricing

Cost per 1M tokens

Claude Opus 5.5
Input
$4.00
Output
$20.00
Gemini 3.1 Flash Lite Preview
Input
$0.25
16× cheaper
Output
$1.50
13× cheaper

Gemini 3.1 Flash Lite Preview is cheaper on both: 16× input, 13× output.

Where to run it

5 hosts

Claude Opus 5.54 hosts
HostInOutContextUptime
Amazon Bedrock$4.00 in·$20.00 out·1M·99.8% upAzure AI Foundry$4.00 in·$20.00 out·1M·100% upAnthropic$4.00 in·$20.00 out·1M·100% upGoogle Vertex AI$4.00 in·$20.00 out·1M·100% up
Gemini 3.1 Flash Lite Preview1 host
HostInOutContextUptime
Google AI Studio$0.25 in·$1.50 out·1M·99.7% up

Per million tokens. Prices and uptime via OpenRouter, checked 25 Sep 2026.

Research

What we learned reading every model

FAQ

Common questions

Claude Opus 5.5 is developed by Anthropic while Gemini 3.1 Flash Lite Preview is developed by Google AI. Claude Opus 5.5 has a 1.0M token context window vs Gemini 3.1 Flash Lite Preview's 1.0M. You can compare their actual outputs across 19 challenges on Rival to see how they differ in practice.

It depends on your use case. Claude Opus 5.5 and Gemini 3.1 Flash Lite Preview each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 19 challenges so you can judge which fits your needs best.

Claude Opus 5.5 costs $4/M input tokens and Gemini 3.1 Flash Lite Preview costs $0.25/M input tokens. Gemini 3.1 Flash Lite Preview is $3.75/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 5.5 and Gemini 3.1 Flash Lite 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

Claude Opus 5.5 logoSolar Mini 4 logo
Claude Opus 5.5 vs Solar Mini 4Landed Sep 2026
Gemini 3.1 Flash Lite Preview logoQwen3.8 Max Prime logo
Gemini 3.1 Flash Lite Preview vs Qwen3.8 Max PrimeLanded Sep 2026
Claude Opus 5.5 logoGLM 5.3 Prime logo
Claude Opus 5.5 vs GLM 5.3 PrimeLanded Sep 2026
Gemini 3.1 Flash Lite Preview logoQwen3.8 Omni Flash logo
Gemini 3.1 Flash Lite Preview vs Qwen3.8 Omni FlashLanded Sep 2026
Claude Opus 5.5 logoCommand A+ logo
Claude Opus 5.5 vs Command A+Landed Sep 2026
Gemini 3.1 Flash Lite Preview logoGPT-6 Luna Pro logo
Gemini 3.1 Flash Lite Preview vs GPT-6 Luna ProLanded Sep 2026
Claude Opus 5.5 logoGPT-6 Sol Pro logo
Claude Opus 5.5 vs GPT-6 Sol ProLanded Sep 2026
Gemini 3.1 Flash Lite Preview logoGPT-6 Luna logo
Gemini 3.1 Flash Lite Preview vs GPT-6 LunaLanded Sep 2026

Same lab, same size, long tail

Claude Opus 5.5 logoClaude Opus 4.6 logo
Claude Opus 5.5 vs Claude Opus 4.6Same lab
Claude Opus 5.5 logoClaude Fable 5.1 logo
Claude Opus 5.5 vs Claude Fable 5.1Same lab
Gemini 3.1 Flash Lite Preview logoGemini 3.1 Pro Preview logo
Gemini 3.1 Flash Lite Preview vs Gemini 3.1 Pro PreviewVersion compare
Gemini 3.1 Flash Lite Preview logoGemini 3.8 Flash logo
Gemini 3.1 Flash Lite Preview vs Gemini 3.8 FlashSame lab
Claude Opus 5.5 logoGemma 4 26B A4B logo
Claude Opus 5.5 vs Gemma 4 26B A4BSame size
Claude Opus 5.5 logoGemma 4 31B logo
Claude Opus 5.5 vs Gemma 4 31BCross-provider
Claude Opus 5.5 logoGLM 4 32B logo
Claude Opus 5.5 vs GLM 4 32BSame size
Claude Opus 5.5 logoGLM 4.5 logo
Claude Opus 5.5 vs GLM 4.5Same size

Model pages

Claude Opus 5.5 logo
Claude Opus 5.519 outputs, specs and price
Gemini 3.1 Flash Lite Preview logo
Gemini 3.1 Flash Lite Preview53 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