GPT-5.5 vs Grok 4.3

Compare GPT-5.5 and Grok 4.3 side by side. See pricing, capabilities, context length, and performance. Use both on Krater.ai from $20/mo.

GPT-5.5 vs Grok 4.3: 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 GPT-5.5 and Grok 4.3 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 · GPT-5.5 on Krater · Grok 4.3 on Krater

What each model is best at

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

Grok 4.3

xAI's Grok 4.3 is the latest flagship in the Grok family, with a 1M-token context window, improved reasoning, and real-time knowledge access. Built for truth-seeking conversation and complex problem solving.

Strengths

  • 1M-token context for huge documents
  • Real-time knowledge access
  • Strong reasoning and analysis
  • Distinctive voice — direct, witty, less hedging

Best for

  • Long-document analysis
  • Conversational research
  • Coding with extended context
  • Real-time fact-checking

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.