Model Comparison
GPT-5 CodexGPT-5.3 Codex
Let's see who can write code better - GPT-5 Codex or GPT-5.3 Codex
Model Information
GPT-5 Codex
Description
Flagship model from OpenAI optimised for coding tasks
Specifications
Context Window272K
Max Output33K
ReleasedSep 2025
API✓
Pricing (per 1M)
In / Out
$1.25/ $10
Key Features
CodingAdvanced reasoningMulti-modal native
Strengths
- ✓State-of-the-art performance
- ✓Optimised for coding
- ✓Large context window
Weaknesses
- ✗Likely very expensive
- ✗Unknown specifications
Agent Support
No known agents
GPT-5.3 Codex
Description
Next-generation coding-optimized model from OpenAI with enhanced autonomous development capabilities
Specifications
Context Window272K
Max Output33K
ReleasedFeb 2026
API✓
Pricing (per 1M)
In / Out
$1.5/ $12
Key Features
Advanced autonomous codingEnhanced code reviewMulti-step reasoningFull-stack development
Strengths
- ✓State-of-the-art coding benchmarks
- ✓Superior autonomous task completion
- ✓Excellent code review capabilities
- ✓Large context window
Weaknesses
- ✗Premium pricing
- ✗Optimized for coding over general tasks
Agent Support
No known agents