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. GPT-5.1 Codex MaxvsQwen3.8 Max Prime
Updated Sep 2026

GPT-5.1 Codex MaxvsQwen3.8 Max Prime

Qwen3.8 Max Prime is the newer model, released after GPT-5.1 Codex Max.

GPT-5.1 Codex Max and Qwen3.8 Max Prime compared across 19 shared prompts
SpecGPT-5.1 Codex MaxQwen3.8 Max Prime
Input price—$4/M tokens
Output price—$12/M tokens
Context window—1.0M tokens
WeightsClosedClosed
Free API (OpenRouter)NoNo
ReleasedDec 2025Sep 2026
Side by side

Same prompt, both answers

Opening lines from 3 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…

GPT-5.1 Codex Max175 words
Sunset Chickpea & Tomato Skillet A cozy, savory one-pan dish that comes together with staples you likely have on hand. Ingredients (7): 1 can (15 oz) chickpeas, drained and rinsed 1 can (14–15 oz) crushed tomatoes 1 medium onion, finely chopped 2 cloves garlic, minced (or 1 tsp garlic powder) 2 tbsp olive oil 1 tsp…
Read the full answer
Qwen3.8 Max Prime223 words
🍯 Golden Hour Noodles A sweet, savory, garlicky pasta that tastes like it took way more effort than it did. Ingredients (7) # Ingredient Amount 1 Spaghetti 8 oz (half a box) 2 Butter 3 tablespoons 3 Garlic, minced 4 cloves 4 Honey 2 tablespoons 5 Soy sauce 1 tablespoon 6 Red pepper flakes ½ teaspoon 7 Parmesan cheese…
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) –…

GPT-5.1 Codex Max192 words
1) Projected cash flows & debt (FY2026–FY2030, $m) (“FCF after debt service” = after interest, taxes, capex, ΔNWC, mandatory amort; applied to optional TL paydown) Year Revenue EBITDA TL Cash Int. Mezz Cash Int. Cash Taxes Capex ΔNWC FCF after debt service End TL Bal. End Mezz Bal. (incl.
Read the full answer
Qwen3.8 Max Prime673 words
HarborTech Services (HTS) – LBO Underwriting Memo Entry & Capital Structure Item Amount FY2025 EBITDA $120.0m Entry Multiple 12.0x Enterprise Value $1,440.0m Transaction Fees (2.0% of EV) $28.8m Total Uses $1,468.8m Term Loan (4.0x, 9.0% cash, 1.0% amort) $480.0m Mezzanine (1.5x, 12.0% cash + 2.0% PIK) $180.0m Sponsor…
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…

GPT-5.1 Codex Max386 words
Here's a simple four‑week framework to help you ease into healthier habits. It keeps the focus on three big levers you can control and builds gradually so it feels doable. Key areas: Nourishing food, regular movement, and rest/recovery.
Read the full answer
Qwen3.8 Max Prime473 words
Your 1-Month Foundation Plan A simple, progressive plan built on three pillars. Each week, you add one small layer. No perfection required—just consistency. 🏃 Pillar 1: Movement Why: Even modest activity reduces all-cause mortality risk and improves mood, sleep, and energy within days.
Read the full answer
Our Verdict
GPT-5.1 Codex Max
GPT-5.1 Codex Max
Qwen3.8 Max Prime
Qwen3.8 Max PrimeRunner-up

Not enough votes to call it. On the specs, GPT-5.1 Codex Max 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

GPT-5.1 Codex Max
Input
—
Output
—
Qwen3.8 Max Prime
Input
$4.00
Output
$12.00
Where to run it

2 hosts

GPT-5.1 Codex Max1 host
HostInOutContextUptime
Azure AI Foundry$1.25 in·$10.00 out·400k·100% up
Qwen3.8 Max Prime1 host
HostInOutContextUptime
Alibaba Cloud$4.00 in·$12.00 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

GPT-5.1 Codex Max is developed by OpenAI while Qwen3.8 Max Prime is developed by Qwen. You can compare their actual outputs across 19 challenges on Rival to see how they differ in practice.

It depends on your use case. GPT-5.1 Codex Max and Qwen3.8 Max Prime 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.

This page shows a side-by-side comparison of GPT-5.1 Codex Max and Qwen3.8 Max Prime 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

GPT-5.1 Codex Max logoSolar Mini 4 logo
GPT-5.1 Codex Max vs Solar Mini 4Landed Sep 2026
Qwen3.8 Max Prime logoGLM 5.3 Prime logo
Qwen3.8 Max Prime vs GLM 5.3 PrimeLanded Sep 2026
GPT-5.1 Codex Max logoQwen3.8 Omni Flash logo
GPT-5.1 Codex Max vs Qwen3.8 Omni FlashLanded Sep 2026
Qwen3.8 Max Prime logoCommand A+ logo
Qwen3.8 Max Prime vs Command A+Landed Sep 2026
GPT-5.1 Codex Max logoClaude Opus 5.5 logo
GPT-5.1 Codex Max vs Claude Opus 5.5Landed Sep 2026
Qwen3.8 Max Prime logoGPT-6 Luna Pro logo
Qwen3.8 Max Prime vs GPT-6 Luna ProLanded Sep 2026
GPT-5.1 Codex Max logoGPT-6 Sol Pro logo
GPT-5.1 Codex Max vs GPT-6 Sol ProLanded Sep 2026
Qwen3.8 Max Prime logoGPT-6 Luna logo
Qwen3.8 Max Prime vs GPT-6 LunaLanded Sep 2026

Same lab, same size, long tail

GPT-5.1 Codex Max logoGPT-6 Luna Pro logo
GPT-5.1 Codex Max vs GPT-6 Luna ProSame lab
GPT-5.1 Codex Max logoGPT-6 Luna logo
GPT-5.1 Codex Max vs GPT-6 LunaSame lab
Qwen3.8 Max Prime logoQwen3.8 Omni Flash logo
Qwen3.8 Max Prime vs Qwen3.8 Omni FlashSame lab
Qwen3.8 Max Prime logoQwen3.7 Flash logo
Qwen3.8 Max Prime vs Qwen3.7 FlashSame lab
Qwen3.8 Max Prime logoClaude Opus 4 logo
Qwen3.8 Max Prime vs Claude Opus 4New provider
Qwen3.8 Max Prime logoClaude Opus 4.1 logo
Qwen3.8 Max Prime vs Claude Opus 4.1New provider
Qwen3.8 Max Prime logoClaude Opus 4.5 logo
Qwen3.8 Max Prime vs Claude Opus 4.5New provider
GPT-5.1 Codex Max logoClaude Opus 4.6 logo
GPT-5.1 Codex Max vs Claude Opus 4.6Same size

Model pages

GPT-5.1 Codex Max logo
GPT-5.1 Codex Max53 outputs, specs and price
Qwen3.8 Max Prime logo
Qwen3.8 Max Prime19 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