Model Comparison

GPT-5GPT-5.3 Codex
Let's see who can write code better - GPT-5 or GPT-5.3 Codex

Model Information

GPT-5

OpenAI

Description

Next-generation flagship model from OpenAI

Specifications

Context Window272K
Max Output33K
ReleasedJun 2025
API

Pricing (per 1M)

In / Out
$1.25/ $10

Key Features

AGI-level capabilitiesAdvanced reasoningMulti-modal native

Strengths

  • State-of-the-art performance
  • Unprecedented capabilities
  • Large context window

Weaknesses

  • Not yet released
  • Likely very expensive
  • Unknown specifications

Agent Support

GPT-5.3 Codex

OpenAI

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