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 MaxvsSolar Mini 4
Updated Sep 2026

GPT-5.1 Codex MaxvsSolar Mini 4

Solar Mini 4 is the newer model, released after GPT-5.1 Codex Max.

GPT-5.1 Codex Max and Solar Mini 4 compared across 19 shared prompts
SpecGPT-5.1 Codex MaxSolar Mini 4
Input price—$0.05/M tokens
Output price—$0.2/M tokens
Context window—524K tokens
WeightsClosed—
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.

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
Solar Mini 41,718 words
518.51935 New TL: 276.34682 - 86.82747 = 189.51935 Mezz: PIK 194.8377888 * 0.02 = 3.896755776 New Mezz: 194.8377888 + 3.896755776 = 198.734544576 Ending Balances: TL: 189.52 Mezz: 198.73 Total Debt: 388.25 Exit (End of FY2030): Exit EBITDA: 206.6252668 Exit Multiple: 10.5x Exit EV: 206.6252668 * 10.5 = 2,169.5653014…
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
Solar Mini 4669 words
Here is a simple, actionable 1-month plan designed for beginners. The focus is on consistency over intensity, meaning small, sustainable changes are better than drastic overhauls that are hard to maintain. The 3 Key Pillars Nutrition: Focus on adding good things rather than strictly restricting.
Read the full answer

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
Solar Mini 4266 words
🌟 Golden Chickpea & Rice Skillet This comforting one-pot dish combines hearty chickpeas, tender rice, and a warm blend of spices. It's a perfect way to use up pantry staples for a quick, flavorful meal.
Read the full answer
Our Verdict
GPT-5.1 Codex Max
GPT-5.1 Codex Max
Solar Mini 4
Solar Mini 4Runner-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
—
Solar Mini 4
Input
$0.05
Output
$0.20
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
Solar Mini 41 host
HostInOutContextUptime
UUpstage$0.05 in·$0.20 out·524k·100% 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 Solar Mini 4 is developed by Upstage. 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 Solar Mini 4 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 Solar Mini 4 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 logoQwen3.8 Max Prime logo
GPT-5.1 Codex Max vs Qwen3.8 Max PrimeLanded Sep 2026
Solar Mini 4 logoGLM 5.3 Prime logo
Solar Mini 4 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
Solar Mini 4 logoCommand A+ logo
Solar Mini 4 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
Solar Mini 4 logoGPT-6 Luna Pro logo
Solar Mini 4 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
Solar Mini 4 logoGPT-6 Luna logo
Solar Mini 4 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
Solar Mini 4 logoSolar Pro 4 logo
Solar Mini 4 vs Solar Pro 4Same lab
Solar Mini 4 logoSolar Pro 3 logo
Solar Mini 4 vs Solar Pro 3Same lab
GPT-5.1 Codex Max logoOpenRouter Fusion · Quality (Jun 2026) logo
GPT-5.1 Codex Max vs OpenRouter Fusion · Quality (Jun 2026)Same size
Solar Mini 4 logoGemini 1.5 Pro logo
Solar Mini 4 vs Gemini 1.5 ProNew provider
Solar Mini 4 logoGemini 2.5 Flash Lite Preview 09-2025 logo
Solar Mini 4 vs Gemini 2.5 Flash Lite Preview 09-2025New provider
Solar Mini 4 logoGemini 2.5 Flash Preview logo
Solar Mini 4 vs Gemini 2.5 Flash PreviewNew provider

Model pages

GPT-5.1 Codex Max logo
GPT-5.1 Codex Max53 outputs, specs and price
Solar Mini 4 logo
Solar Mini 419 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