CourionAI Newsletter
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GPT-5.5

OpenAI's 2025 flagship model, predecessor of the GPT-5.6 family.

GPT-5.5 was OpenAI’s flagship model before the GPT-5.6 generation arrived in mid-2026. It still powers parts of ChatGPT, including portions of the free tier.

Model names change fast; what matters for readers is the pattern. Each generation gets cheaper per unit of capability, and yesterday’s flagship becomes today’s free tier.