OpenAI launches ChatGPT
OpenAI released ChatGPT, a conversational interface to a GPT-3.5 model fine-tuned with RLHF, as a free research preview; it became the fastest-growing consumer app to that point and triggered the generative AI boom.
Key facts
- Launched 30 November 2022 as a free research preview
- Based on a model in the GPT-3.5 series, trained with RLHF
- Passed 1 million users within about five days
- Estimated at ~100M monthly users by January 2023 (UBS/Similarweb estimate)
- ChatGPT Plus ($20/month) launched February 2023
What happened
ChatGPT let anyone chat with a capable LLM for free; its viral success forced Google, Meta, Microsoft and others into an AI race.
Why it matters
The moment AI became a mass-market technology — the start of the current era of AI investment, adoption and policy attention.
Changelog
- 2026-09-29: created
Related events
- InstructGPT: RLHF aligns language models to follow instructions ★★★★★
- OpenAI releases GPT-4 ★★★★★
- ELIZA, the first chatbot, published by Joseph Weizenbaum ★★★★
- OpenAI founded as a non-profit AI research lab ★★★★
- GPT-3 (175B) shows in-context few-shot learning ★★★★★
Sources (2)
id: 2022-11-30-chatgpt · updated 2026-09-29 · open in the interactive timeline