Model Comparison

Claude Opus 4.5GPT-5 Codex
Let's see who can write code better - Claude Opus 4.5 or GPT-5 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 Codex

OpenAI

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