Compare Claude Sonnet 4.5 and GPT-5.2 Pro side by side. See pricing, capabilities, context length, and performance. Use both on Krater.ai from $20/mo.
Claude Sonnet 4.5 vs GPT-5.2 Pro: 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.
Run Claude Sonnet 4.5 and GPT-5.2 Pro 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 Sonnet 4.5 on Krater · GPT-5.2 Pro on Krater
A major update to the Claude Sonnet line, offering near-Opus-level reasoning with significantly faster response times. Claude Sonnet 4.5 is the sweet spot of capability and speed.
The premium tier of OpenAI's GPT-5.2, offering maximum capability and reasoning depth. GPT-5.2 Pro is designed for the most demanding professional and research applications.
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.