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 5.5vsQwen3.5 Flash
Updated Sep 2026

Claude Opus 5.5vsQwen3.5 Flash

Qwen3.5 Flash is cheaper than Claude Opus 5.5 at $0.1/M vs $4/M input tokens.

Claude Opus 5.5 and Qwen3.5 Flash compared across 19 shared prompts
SpecClaude Opus 5.5Qwen3.5 Flash
Input price$4/M tokens$0.1/M tokens
Output price$20/M tokens$0.4/M tokens
Context window1.0M tokens1.0M tokens
WeightsClosedClosed
Free API (OpenRouter)NoNo
ReleasedSep 2026Feb 2026
Side by side

Same prompt, both answers

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

Simple 7-Ingredient Recipe

Create a simple recipe for a delicious dish (sweet or savory) using only 7 common pantry ingredients. Include a creative name for the dish…

Claude Opus 5.5300 words
Midnight Silk Noodles Creamy, tangy peanut noodles with a gentle kick, ready faster than takeout. Serves: 2 Prep time: 5 minutes Cook time: 10 minutes Total time: 15 minutes The 7 Ingredients 8 oz (225 g) spaghetti (or any long noodle) ¼ cup creamy peanut butter 3 tablespoons soy sauce 1 tablespoon honey (or sugar) 1…
Read the full answer
Qwen3.5 Flash270 words
🍜 Golden Lightning Noodles Description: A quick, creamy, and savory-sweet noodle dish that packs a punch of flavor using staples you likely already have. The peanut butter creates a velvety sauce, while the vinegar and chili add a necessary zing to cut through the richness.
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
Qwen3.5 Flash507 words
DISCLAIMER: I am an AI, not a doctor or healthcare provider. The following plan involves advanced physiological interventions, including metabolic manipulation, supplementation, and fasting. These strategies carry risks and may interact with medications or pre-existing conditions.
Read the full answer

Beginner's Longevity Plan

Outline a simple, actionable 1-month plan for someone starting their journey towards better health and longevity. Focus on 3 key areas…

Claude Opus 5.5653 words
Your 1-Month Starter Plan for Better Health & Longevity The philosophy: Small, consistent changes beat dramatic overhauls. Each week builds on the last, so by Day 30 you'll have a foundation of habits instead of a burned-out resolution.
Read the full answer
Qwen3.5 Flash614 words
The 30-Day Longevity Launchpad Goal: Build sustainable habits that reduce inflammation, improve energy, and extend healthspan. Mindset: Consistency beats intensity. Do not aim for perfection; aim for showing up. The 3 Core Pillars Nutrition: "Add, Don't Subtract" Focus on nutrient density rather than calorie counting.
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
Qwen3.5 Flash1,249 words
This architecture is a common "MVP" design, but it contains several critical flaws that would prevent it from functioning as a true real-time collaborative editor (like Google Docs) under load. The most severe issues relate to data integrity (sync strategy) and real-time consistency (network topology).
Read the full answer

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
Qwen3.5 Flash520 words
HarborTech Services (HTS) – 5-Year LBO Underwriting Analysis Investment Summary Initial Equity Check: $808.8m Calculation: EV ($1,440m) + Fees ($28.8m) - Debt ($660m). Entry Leverage: 5.5x EBITDA ($660m Total Debt). Exit Leverage: ~2.0x EBITDA ($415.7m Total Debt).
Read the full answer

Adversarial Contract Review

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

Claude Opus 5.54,420 words
Contractor-Side Review of the Software Consulting Agreement Overall assessment: This agreement is heavily one-sided. Nearly every clause shifts risk, cost, or control to the Contractor, and several provisions interact to create compounding exposure.
Read the full answer
Qwen3.5 Flash1,374 words
Disclaimer: I am an AI, not an attorney. This analysis is for informational purposes only and does not constitute legal advice. Contract laws vary significantly by jurisdiction (e.g., California vs. New York vs. UK).
Read the full answer
Our Verdict
Claude Opus 5.5
Claude Opus 5.5
Qwen3.5 Flash
Qwen3.5 FlashRunner-up

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

Qwen3.5 Flash costs 50x less per token.

Slight edge

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
Qwen3.5 Flash
Input
$0.10
40× cheaper
Output
$0.40
50× cheaper

Qwen3.5 Flash is cheaper on both: 40× input, 50× 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
Qwen3.5 Flash1 host
HostInOutContextUptime
Alibaba Cloud$0.07 in·$0.26 out·1M·99.9% 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 Qwen3.5 Flash is developed by Qwen. Claude Opus 5.5 has a 1.0M token context window vs Qwen3.5 Flash'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 Qwen3.5 Flash 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 Qwen3.5 Flash costs $0.1/M input tokens. Qwen3.5 Flash is $3.90/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 Qwen3.5 Flash 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
Qwen3.5 Flash logoQwen3.8 Max Prime logo
Qwen3.5 Flash 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
Qwen3.5 Flash logoQwen3.8 Omni Flash logo
Qwen3.5 Flash vs Qwen3.8 Omni FlashLanded Sep 2026
Claude Opus 5.5 logoCommand A+ logo
Claude Opus 5.5 vs Command A+Landed Sep 2026
Qwen3.5 Flash logoGPT-6 Luna Pro logo
Qwen3.5 Flash 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
Qwen3.5 Flash logoGPT-6 Luna logo
Qwen3.5 Flash 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
Qwen3.5 Flash logoQwen3.5 122B A10B logo
Qwen3.5 Flash vs Qwen3.5 122B A10BVersion compare
Qwen3.5 Flash logoQwen3.7 Flash logo
Qwen3.5 Flash vs Qwen3.7 FlashSame lab
Claude Opus 5.5 logoCypher Alpha (free) logo
Claude Opus 5.5 vs Cypher Alpha (free)Same size
Claude Opus 5.5 logoDeepSeek V3.1 logo
Claude Opus 5.5 vs DeepSeek V3.1New provider
Qwen3.5 Flash logoDeepSeek Prover V2 logo
Qwen3.5 Flash vs DeepSeek Prover V2New provider
Claude Opus 5.5 logoDeepSeek R1 logo
Claude Opus 5.5 vs DeepSeek R1Same size

Model pages

Claude Opus 5.5 logo
Claude Opus 5.519 outputs, specs and price
Qwen3.5 Flash logo
Qwen3.5 Flash53 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