OpenAI announced on Tuesday that it’s replacing the default model in ChatGPT with GPT-5.5 Instant, which the company says produces faster responses, shorter answers, and fewer incorrect claims.

In this breaking story, TNS contributor Paul Sawers explains that the new model follows GPT-5.3 Instant, which was introduced in March. This new Instant model is designed for everyday tasks such as writing, analysis, and general queries. OpenAI says in a blog post published Tuesday afternoon that “accuracy” is the model’s core selling point.

“Instant is now more dependable, with significant improvements in factuality across the board and the largest gains in domains where accuracy matters most,” the company writes.

OpenAI is highlighting improvements in accuracy, but it has not provided detailed benchmarks or independent comparisons, Sawers reports. The claim rests largely on internal evaluation, leaving open questions about how the model performs across different domains.

Read the full story: OpenAI rolls out GPT-5.5 Instant as default ChatGPT model — and promises more accurate responses

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