ChatGPT-5.1 Rollout Begins: OpenAI’s Latest Models to Reach Pro, Plus, and Enterprise Users First

By Oneindia Staff

Updated: Thursday, November 13, 2025, 9:28 [IST]

OpenAI is introducing GPT-5.1, enhancing its main model with two advanced versions: GPT-5.1 Instant and GPT-5.1 Thinking. These updates aim to provide more engaging conversations and improved instruction-following capabilities. This release comes three months after the challenging launch of GPT-5 in August, which faced criticism for being less effective than previous versions.

GPT-5.1 Instant is designed for most ChatGPT interactions, offering quicker and more natural dialogues. Meanwhile, GPT-5.1 Thinking is tailored for solving complex issues through extended reasoning. Both models can assess the difficulty of questions dynamically, dedicating more resources to challenging queries while providing swift responses to simpler ones.

AI Summary

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OpenAI is releasing GPT-5.1, featuring GPT-5.1 Instant and GPT-5.1 Thinking, with enhanced conversational abilities and instruction following; it includes eight personality modes and improvements in math and coding, with early access for Pro, Plus, Go, and Business subscribers and a phased API rollout.

Enhanced Personalities and User Experience

The new version introduces eight personality modes: Default, Professional, Friendly, Candid, Quirky, Efficient, Nerdy, and Cynical. Users can also fine-tune response warmth and emoji usage. These adjustments are applied instantly across all chats, both existing and new.

Subscribers on Pro, Plus, Go, and Business plans will have early access to these features. Free accounts will follow shortly after. Enterprise and Education plans will enjoy a week-long preview before GPT-5.1 becomes the standard offering. The older GPT-5 models will remain available for three months in a dropdown menu for paying users.

Improvements in Math and Coding

OpenAI claims that GPT-5.1 has made notable advancements in math and coding tests such as AIME 2025 and Codeforces. The GPT-5.1 Thinking model simplifies complex concepts by removing technical jargon and explaining them in straightforward language.

The company highlighted that users desire an AI that is "not only smart but also enjoyable to talk to." Fidji Simo, CEO of Applications at OpenAI, mentioned that this update strikes a balance between intelligence and approachability.

The new models will be available on the API later this week with a phased rollout over several days to ensure platform stability.