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
  • 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-5.3-CodexvsSolar Pro 4
Updated Aug 2026

GPT-5.3-CodexvsSolar Pro 4

Solar Pro 4 is cheaper than GPT-5.3-Codex at $0.09/M vs $1.75/M input tokens.

GPT-5.3-Codex and Solar Pro 4 compared across 14 shared prompts
SpecGPT-5.3-CodexSolar Pro 4
Input price$1.75/M tokens$0.09/M tokens
Output price$14/M tokens$0.36/M tokens
Context window400K tokens524K tokens
WeightsClosed—
Free API (OpenRouter)NoNo
ReleasedFeb 2026Aug 2026
Side by side

Same prompt, both answers

Opening lines from 6 of the 14 prompts both answered. Formatting stripped, words untouched.

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.…

GPT-5.3-Codex429 words
Great concept, but three claims stand out as especially weak from an investor diligence perspective: “MindMeld AI reads your brainwaves to predict what you want to type before you think it.” (Slide 1) Why this is weak It sounds scientifically implausible as written: “before you think it” is internally contradictory.
Read the full answer
Solar Pro 41,009 words
Here are the three weakest claims in the MindMeld AI pitch deck, along with an analysis of why they undermine credibility and specific recommendations for improvement. The Technical Performance Claim Claim: "Our proprietary EEG headband uses advanced ML to decode neural patterns into text with 94% accuracy...
Read the full answer

Historical Counterfactual Analysis

If the transistor had been invented in 1920 instead of 1947, trace the likely technological, economic, and geopolitical implications through…

GPT-5.3-Codex785 words
Great counterfactual. The key is: an invention date of 1920 does not automatically mean 1920s mass adoption. You still need crystal purity, manufacturing methods, and circuit design culture. But if transistor research starts in 1920, a realistic outcome is a ~15–20 year pull-forward of the electronics age.
Read the full answer
Solar Pro 41,638 words
The Premise: The 1920 Solid-State Breakthrough For this scenario to function, we must assume a functional point-contact or junction transistor is demonstrated in 1920 (perhaps by Lilienfeld or an early Bell Labs precursor), and crucially, that methods for purifying semiconductor materials (germanium/silicon) are solved…
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…

GPT-5.3-Codex1,009 words
LedgerLift (LLLT) – IC Memo (Fictional) Recommendation: PASS (bias: valuation-risk skew to downside on intrinsic basis) Current Price: $46 12-mo PT range (fair value): $30–$48 (midpoint ~$38) 2-sentence thesis: LedgerLift screens as a high-quality vertical SaaS asset (92% subscription mix, 123% NRR, 6% logo churn…
Read the full answer
Solar Pro 41,052 words
INTERNAL MEMO – INVESTMENT COMMITTEE TO: IC Members FROM: Long/Short Equity Desk DATE: Oct 2024 SUBJECT: LedgerLift (LLLT) – Initiation / Long Recommendation & Thesis Recommendation: LONG 12-Month PT Range: $52–$58 (Base case ~$54, Bull ~$68, Bear ~$38) Thesis: LedgerLift is a structurally advantaged mid-market AP…
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-5.3-Codex203 words
Recipe: “Weeknight Volcano Pasta” 🌋🍝 A cozy, spicy-savory pasta made from pantry staples in about 25 minutes. Ingredients (7 pantry items) 8 oz dried pasta (any shape) 1 can (15 oz) cannellini or great northern beans, drained 1 can (14–15 oz) crushed tomatoes 2 tbsp olive oil 1 tsp garlic powder 1 tsp dried oregano…
Read the full answer
Solar Pro 4294 words
🍝 Golden Umami Silk Noodles A savory-sweet pasta dish that transforms basic pantry staples into a glossy, flavorful meal. It's quick, comforting, and relies on the balance of soy, honey, and butter for a rich sauce without needing fresh produce.
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…

GPT-5.3-Codex915 words
I would not wait. This is a textbook “patient safety + material disclosure” crisis. The right move is rapid, documented, regulator-first action. Immediate stance (set at Hour 0) Patient safety first (interim risk controls now, not after perfect certainty).
Read the full answer
Solar Pro 41,851 words
As CEO, my overriding duty is to balance patient safety, legal/regulatory compliance, fiduciary responsibility, and long-term corporate survival. A 1-in-8,000 risk of liver failure is rare but severe, potentially fatal, and materially unexpected relative to the current label.
Read the full answer

Explain Like I'm a Specific Expert

Explain how a large language model (like GPT or Claude) learns and generates text to each of these three audiences: 1. **An experienced…

GPT-5.3-Codex600 words
For the experienced software engineer Think of an LLM as a very large, probabilistic autocomplete service trained on a massive corpus of text and code. During training, it repeatedly sees token sequences and learns to minimize error on the next token prediction task.
Read the full answer
Solar Pro 41,062 words
The Experienced Software Engineer Think of the model not as a reasoning engine, but as a highly compressed, non-deterministic function approximator that maps a sequence of input tokens to a probability distribution over the next token.
Read the full answer
Our Verdict
GPT-5.3-Codex
GPT-5.3-Codex
Solar Pro 4
Solar Pro 4Runner-up

Not enough votes to call it. On the specs, GPT-5.3-Codex has the edge: bigger model tier, major provider backing.

Solar Pro 4 costs 39x less per token.

Too close to call
API pricing

Cost per 1M tokens

GPT-5.3-Codex
Input
$1.75
Output
$14.00
Solar Pro 4
Input
$0.09
19× cheaper
Output
$0.36
39× cheaper

Solar Pro 4 is cheaper on both: 19× input, 39× output.

Where to run it

3 hosts

GPT-5.3-Codex2 hosts
HostInOutContextUptime
Azure AI Foundry$1.75 in·$14.00 out·400k·100% upOpenAI$1.75 in·$14.00 out·400k·100% up
Solar Pro 41 host
HostInOutContextUptime
UUpstage$0.09 in·$0.36 out·524k·99.8% up

Per million tokens. Prices and uptime via OpenRouter, checked 22 Sep 2026.

Research

What we learned reading every model

FAQ

Common questions

GPT-5.3-Codex is developed by OpenAI while Solar Pro 4 is developed by Upstage. GPT-5.3-Codex has a 400K token context window vs Solar Pro 4's 524K. You can compare their actual outputs across 14 challenges on Rival to see how they differ in practice.

It depends on your use case. GPT-5.3-Codex and Solar Pro 4 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 14 challenges so you can judge which fits your needs best.

GPT-5.3-Codex costs $1.75/M input tokens and Solar Pro 4 costs $0.09/M input tokens. Solar Pro 4 is $1.66/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 GPT-5.3-Codex and Solar Pro 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-5.3-Codex logoDeepSeek V4 Flash Vision Exp logo
GPT-5.3-Codex vs DeepSeek V4 Flash Vision ExpLanded Sep 2026
Solar Pro 4 logoHy3 logo
Solar Pro 4 vs Hy3Landed Sep 2026
GPT-5.3-Codex logoQwen3.7 Flash logo
GPT-5.3-Codex vs Qwen3.7 FlashLanded Sep 2026
Solar Pro 4 logoLing 3.0 Flash logo
Solar Pro 4 vs Ling 3.0 FlashLanded Sep 2026
GPT-5.3-Codex logoMuse Glimmer 30B logo
GPT-5.3-Codex vs Muse Glimmer 30BLanded Sep 2026
Solar Pro 4 logoGLM 5.3 logo
Solar Pro 4 vs GLM 5.3Landed Sep 2026
GPT-5.3-Codex logoTernary Bonsai 2 27B logo
GPT-5.3-Codex vs Ternary Bonsai 2 27BLanded Sep 2026
Solar Pro 4 logoGLM 5.3 Flash logo
Solar Pro 4 vs GLM 5.3 FlashLanded Sep 2026

Same lab, same size, long tail

GPT-5.3-Codex logoGPT-6 Astra Pro logo
GPT-5.3-Codex vs GPT-6 Astra ProSame lab
GPT-5.3-Codex logoGPT-6 Astra logo
GPT-5.3-Codex vs GPT-6 AstraSame lab
Solar Pro 4 logoSolar Pro 3 logo
Solar Pro 4 vs Solar Pro 3Same lab
Solar Pro 4 logoOx Alpha logo
Solar Pro 4 vs Ox AlphaSame size
Solar Pro 4 logoNVIDIA Nemotron 3 Super (free) logo
Solar Pro 4 vs NVIDIA Nemotron 3 Super (free)Same size
Solar Pro 4 logoNemotron 3 Ultra logo
Solar Pro 4 vs Nemotron 3 UltraNew provider
Solar Pro 4 logoNemotron 3.5 Content Safety logo
Solar Pro 4 vs Nemotron 3.5 Content SafetyNew provider
Solar Pro 4 logoNemotron 3.5 Lightning logo
Solar Pro 4 vs Nemotron 3.5 LightningNew provider

Model pages

GPT-5.3-Codex logo
GPT-5.3-Codex53 outputs, specs and price
Solar Pro 4 logo
Solar Pro 414 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
  • 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