Model Comparison

Claude Opus 4.5GPT-5.3 Codex
Let's see who can write code better - Claude Opus 4.5 or GPT-5.3 Codex

Model Information

Claude Opus 4.5

Anthropic

Description

Most advanced Claude model with enhanced capabilities

Specifications

Context Window200K
Max Output8K
ReleasedNov 2025
API

Pricing (per 1M)

In / Out
$5/ $25

Key Features

State-of-the-art reasoningAdvanced code generationComplex problem solvingMulti-language supportVision capabilities

Strengths

  • More affordable than 4.1
  • Superior reasoning abilities
  • Excellent at complex tasks
  • Most advanced Claude model

Weaknesses

  • Higher cost
  • Slower response times
  • Overkill for simple tasks

Agent Support

No known agents

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