GPT-5 line

weights

closed

data

closed

code

closed

license

Proprietary(API + ChatGPT only)

GPT-5 has no downloadable weights, no published training data, and no published training code: it is served only through the OpenAI API and ChatGPT. The later releases, GPT-5.5 and GPT-5.6, and the GPT-6 family that followed in September 2026 are listed as proprietary in the same way.

• https://en.wikipedia.org/wiki/GPT-5 recorded 2026-09-29

  Wikipedia GPT-5 article: infobox license field reads "[[Proprietary software|Proprietary]]" and the lead says GPT-5 "It is publicly accessible to users of the" chatbot products and developers through the API, i.e. hosted access only. Searched the body for open weights release, training data release, published training code and source code: none offered.

• https://en.wikipedia.org/wiki/GPT-5.6 recorded 2026-09-29

  Wikipedia GPT-5.6 article: infobox license "[[Proprietary software|Proprietary]]", predecessor GPT-5.5, successor GPT-6; "Luna, Terra, and Sol" variants. Searched the body for open weights, training data release, published code and open source: none.

• https://en.wikipedia.org/wiki/GPT-6 recorded 2026-09-29

  Wikipedia GPT-6 article: infobox license "[[Proprietary software|Proprietary]]"; GPT-6 is an OpenAI model family with Astra released "to the general public on September 4, 2026" and Sol and Luna on September 22, 2026. Searched the body for open weights, training data release, published code and open source: none.

• https://platform.openai.com/docs/models/gpt-5 recorded 2026-09-29

  OpenAI API docs model page for GPT-5 describes API model snapshots ("Snapshots let you lock in a specific version of the model so that performance and behavior remain consistent"), i.e. a hosted API model. Searched the body for download, open weights, license, training data and source code: none.

GPT-5 was the default model behind ChatGPT for logged-in users after its August 2025 launch, so its usage is attributed to the ChatGPT surface rather than to a standalone download or install count. ChatGPT's user numbers describe the product as a whole rather than GPT-5 alone, and its engine is now GPT-6 Astra.

• https://en.wikipedia.org/wiki/ChatGPT recorded 2026-09-29

  Wikipedia ChatGPT article reports that "In February 2026, ChatGPT reached 900 million weekly active users." and lists GPT-6 September 2026 as the current release with Luna, Sol and Astra versions.

OpenAI reported SWE-bench Verified 74.9%, MMMU 84.2%, AIME 2025 94.6% without tools and Aider Polyglot 88% at launch, which were frontier-tier results at the time; the figures are vendor-reported. OpenAI has since released GPT-5.6 and GPT-6.

• https://cdn.openai.com/gpt-5-system-card.pdf recorded 2026-08-14

  OpenAI GPT-5 system card - "The SWE-Bench result in the GPT-5 launch blog post (74.9%), was run with the default verbosity setting in the API (verbosity = medium)"; "All SWE-bench evaluation runs use a fixed subset of n=477 verified tasks". Confirms the SWE-bench Verified basis figure from OpenAI directly. Carries no MMMU, AIME 2025 or Aider Polyglot headline.

• https://openai.com/index/introducing-gpt-5/ recorded 2026-08-14

  OpenAI's GPT-5 launch post, the source of the four recorded figures, all four present in the body as fetched