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20262020s
GPT-5.5
OpenAI released GPT-5.5 (codename 'Spud') on April 23, 2026, billing it as its smartest and most intuitive model to date.
Why It Mattered
GPT-5.5 consolidated OpenAI's rapid post-GPT-5 release cadence, becoming ChatGPT's default for free users in May 2026 and spawning specialized variants including the limited-preview GPT-5.5-Cyber for vetted cybersecurity teams. The release underscored the industry's shift from monolithic annual launches to continuous point releases, with capability gains delivered incrementally across consumer, developer, and safety-restricted channels.
Who Built It
OpenAI
Applications
- General Assistance
- Coding
- Cybersecurity