GPT

7 entries between May 2020 and August 2025, 3 turning points, 15 releases.

Turning points

  1. OpenAI launches GPT-4o, a single model for text, audio, and images

    OpenAI introduced GPT-4o on 13 May 2024, one model trained across text, image, and audio, demonstrated by chief technology officer Mira Murati in a livestream showing real-time voice conversation. OpenAI gave it to free ChatGPT users and said it handled around 50 languages.

  2. OpenAI releases GPT-4, its first model to accept images

    OpenAI released GPT-4 on 14 March 2023 to ChatGPT Plus subscribers and to developers through a waitlist. The model accepted images as well as text. OpenAI reported it placing near the top 10 percent on a simulated bar exam, against roughly the bottom 10 percent for GPT-3.5.

  3. OpenAI publishes GPT-3, a 175-billion-parameter language model

    OpenAI researchers led by Tom B. Brown posted “Language Models are Few-Shot Learners” to arXiv on 28 May 2020. It described GPT-3, an autoregressive language model with 175 billion parameters, ten times larger than any prior non-sparse model.

Every entry

  1. OpenAI makes GPT-5 the default model in ChatGPT

    OpenAI released GPT-5 on 7 August 2025, describing it as a unified model that combined the step-by-step reasoning of the o-series with the faster replies of the GPT series, with a 400,000-token context window. It became the default for free and paid ChatGPT users.

  2. OpenAI launches GPT-4o, a single model for text, audio, and images

    OpenAI introduced GPT-4o on 13 May 2024, one model trained across text, image, and audio, demonstrated by chief technology officer Mira Murati in a livestream showing real-time voice conversation. OpenAI gave it to free ChatGPT users and said it handled around 50 languages.

  3. OpenAI releases GPT-4, its first model to accept images

    OpenAI released GPT-4 on 14 March 2023 to ChatGPT Plus subscribers and to developers through a waitlist. The model accepted images as well as text. OpenAI reported it placing near the top 10 percent on a simulated bar exam, against roughly the bottom 10 percent for GPT-3.5.

  4. OpenAI announces Codex, a code-generating version of GPT-3

    OpenAI announced Codex on 10 August 2021 and opened a private beta. The model, a version of GPT-3 fine-tuned on public source code, turned plain-English instructions into working code across several programming languages in live demonstrations.

  5. Microsoft licenses GPT-3 exclusively from OpenAI

    Microsoft announced a multiyear agreement on 22 September 2020 to license GPT-3 exclusively, letting it embed the model in its own products while OpenAI continued to sell GPT-3 to other customers through its own API. Azure already hosted OpenAI’s training supercomputer.

  6. OpenAI opens GPT-3 to developers through a private API beta

    OpenAI opened a commercial API on 11 June 2020 giving developers access to GPT-3 for what it called virtually any English language task. The private beta included about a dozen partner companies, among them Algolia, Quizlet, and Reddit.

  7. OpenAI publishes GPT-3, a 175-billion-parameter language model

    OpenAI researchers led by Tom B. Brown posted “Language Models are Few-Shot Learners” to arXiv on 28 May 2020. It described GPT-3, an autoregressive language model with 175 billion parameters, ten times larger than any prior non-sparse model.

Releases

Date Release Maker Kind What it was
2026
GPT-Rosalind (out of research preview) OpenAI model Life sciences research model introduced in April; left research preview and became available globally to eligible organizations via trusted access.
GPT-Live-1 in the API OpenAI model Voice model that listens and speaks at once, first introduced in ChatGPT, handing deeper reasoning to paired models; $0.05 per minute for the voice layer.
GPT-Image-2.5 Flare OpenAI model API image model with the quality, editing and speed improvements of Images 2.5.
GPT-Image-2.5 Sunburst OpenAI model API image model with extra precision for detailed creative work, at the cost of longer generation times.
GPT-6 Astra OpenAI model Model aimed at computer use, browsing, software engineering, cybersecurity and science; initially rolled out to a limited set of organizations.
GPT-5.6 Luna OpenAI model New default model for free-tier ChatGPT.
GPT-5.3 Codex OpenAI model Agentic coding model, 25% faster than GPT-5.2; released 15 minutes after Opus 4.6.
2025
GPT-5 OpenAI model OpenAI’s first unified reasoning-plus-chat model. Became the default in ChatGPT.
GPT-4.5 OpenAI model OpenAI’s largest chat model at release, later positioned as a step toward GPT-5.
2024
GPT-4o OpenAI model Native text, audio and vision in one model; free ChatGPT tier access.
2023
GPT-4 OpenAI model Multimodal (text and image) model; technical report on arXiv.
2020
GPT-3 (“Language Models are Few-Shot Learners”) OpenAI paper 175-billion-parameter language model. Access sold through an API; the weights were withheld.
2019
GPT-2 (1.5B, full) OpenAI model, open weights The complete model and code, released after a nine-month staged rollout.
GPT-2 (124M, staged) OpenAI model, open weights The small model and its code published openly; the full 1.5-billion-parameter version withheld, citing the risk of misuse.
2018
GPT-1 OpenAI paper, open weights Generative pretraining on unlabeled text followed by task fine-tuning, the pattern later scaled through the GPT series.