GPT-5.2 o1 vs Sonnet 4.5

A detailed comparison to help you choose the right AI tool for your needs.

Winner
OpenAI

GPT-5.2 Thinking

4.9
Try GPT-5.2 o1
Anthropic

Claude Sonnet 4.5

4.8
Try Sonnet 4.5
Our Pick
GPT-5.2 Thinking

GPT-5.2 Thinking edges out Claude Sonnet 4.5 with superior overall performance and features that make it the better choice for most users.

Try GPT-5.2 o1

Feature Comparison

Feature
GPT-5.2 o1
Sonnet 4.5
Ratings
Overall Rating
4.9
4.8
Coding
4.8
4.7
Writing
4.5
4.9
Reasoning
5.0
4.7
Speed
3.8
4.6
Value
4.0
4.9
Pricing
Monthly Price
$200
$20
Free Tier
Input (per 1M tokens)
$15
$3
Output (per 1M tokens)
$60
$15
Features
Context Window
128K
200K
Vision/Images
Audio
Video
Code Generation
AI Agents

GPT-5.2 Thinking

Pros

  • Best reasoning model from OpenAI
  • Edges out Gemini 3 and Claude Opus 4.5 on most tests
  • Performs at/above human expert level on GDPval
  • Excellent for coding, math, and document analysis
  • State-of-the-art on SWE-Bench Pro

Cons

  • Expensive ($200/mo for Pro subscription)
  • Slower than Instant variant
  • Requires Pro subscription for full access
  • Writing can feel robotic

Claude Sonnet 4.5

Pros

  • Best value for money
  • Excellent writing quality
  • Fast response times
  • Strong coding abilities
  • Free tier available

Cons

  • Not as powerful as Opus for complex tasks
  • Usage limits on free tier

Choose GPT-5.2 o1 if you need:

Complex reasoning, software engineering, research, math proofs

Choose Sonnet 4.5 if you need:

Daily coding tasks, writing, general use

Ready to get started?

Both tools offer free tiers or trials. Try them out and see which one works best for your workflow.