Claude Haiku 4.5 vs GPT-5.5

Compare Claude Haiku 4.5 and GPT-5.5 side by side. See pricing, capabilities, context length, and performance. Use both on Krater.ai from $20/mo.

Claude Haiku 4.5 vs GPT-5.5: strengths, best use cases and how to run both side by side. The live page adds context windows, token pricing and more comparisons once it loads.

Try both on Krater

Run Claude Haiku 4.5 and GPT-5.5 on the same prompt in the Krater Model Arena, then keep the winner in your workflow. One subscription covers both, from $20 a month.

Open Krater chat · Claude Haiku 4.5 on Krater · GPT-5.5 on Krater

What each model is best at

Claude Haiku 4.5

The newest and fastest model in the Claude family. Claude Haiku 4.5 delivers impressive capabilities at lightning speed, perfect for real-time applications and high-volume usage.

Strengths

  • Ultra-fast response times
  • Previous-gen Sonnet-level quality
  • Very cost-effective
  • Strong coding for its speed tier

Best for

  • Real-time chat applications
  • High-volume API usage
  • Quick coding assistance
  • Cost-sensitive deployments

GPT-5.5

OpenAI's GPT-5.5 is the next-generation flagship model with a 1M-token context window, sharper reasoning, and improved instruction following over GPT-5.3. Available now on Krater alongside 500+ other AI models.

Strengths

  • Frontier reasoning across math, code, and analysis
  • 1M-token context for long documents and codebases
  • Improved instruction following and steerability
  • Strong multimodal understanding (text + vision)

Best for

  • Complex multi-step reasoning tasks
  • Long-document analysis and summarization
  • Production-grade coding assistance
  • Agentic workflows with tool use

How we compare models

Our tested head-to-heads run the same prompt set through both models in the Model Arena, then rank answers blind. Read the testing methodology, or browse every comparison.