5OpenAI Release Notes·
OpenAI deprecates Atlas browser agent, consolidating capabilities into ChatGPT and Codex
OpenAI is retiring Atlas, its standalone browser-based agentic product, effective August 9, 2026. Browser agentic capabilities are being folded into ChatGPT and Codex, with an enhanced browser experience (multiple tabs, downloads, account login) planned for ChatGPT. Users must manually export Atlas data such as bookmarks and passwords before the shutdown date, as no automatic transfer is provided.
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Related events (8)
How we built OWL, the new architecture behind our ChatGPT-based browser, Atlas
OpenAI published a technical deep dive into OWL, the architecture underpinning ChatGPT Atlas, a new Chromium-based browser. The post covers how OWL decouples Chromium internals to enable fast startup, rich UI rendering, and agentic browsing capabilities integrated with ChatGPT. This represents OpenAI's move into the browser layer as an agentic interface, extending ChatGPT's reach into web navigation and task execution.
OpenAI retires GPT-4.5 from ChatGPT, transitions users to GPT-5.5
As of June 26, 2026, GPT-4.5 is no longer available in ChatGPT or custom GPTs, with existing conversations migrating to GPT-5.5. The retirement was pre-announced on May 28, 2026 and does not affect API access. This marks a consolidation of OpenAI's ChatGPT model lineup around the GPT-5.5 generation.
OpenAI deprecates older GPT-5 and Codex model variants in ChatGPT
OpenAI is removing six model variants from the ChatGPT model picker starting April 7, 2026, including gpt-5.2-codex, gpt-5.1-codex-mini, gpt-5.1-codex-max, gpt-5.1-codex, gpt-5.1, and gpt-5, with full removal from Codex on April 14. Users are directed toward gpt-5.4, gpt-5.4-mini, gpt-5.3-codex, and gpt-5.2 as the supported options, with gpt-5.3-codex-spark available to Pro subscribers. The update signals OpenAI consolidating its model lineup around newer GPT-5.x variants and retiring earlier iterations.
OpenAI retiring o3 and GPT-4.5 from ChatGPT
OpenAI announced the retirement of two models from ChatGPT: GPT-4.5 on June 27, 2026 (30-day sunset) and o3 on August 26, 2026 (90-day sunset). Both models are currently available only to paid users via model settings. The retirements apply to ChatGPT only; API access is unaffected.
OpenAI Retiring GPT-4o, GPT-4.1, GPT-4.1 mini, and o4-mini from ChatGPT in February 2026
OpenAI announced that on February 13, 2026, it will retire GPT-4o, GPT-4.1, GPT-4.1 mini, and o4-mini from ChatGPT, alongside the previously announced retirement of GPT-5 variants (Instant, Thinking, and Pro). The retirements apply only to the ChatGPT product interface; API access to these models is unaffected at this time. This signals a consolidation of the ChatGPT model lineup, likely in favor of newer or more capable successors.
OpenAI launches Codex Chrome extension for browser-based agentic tasks
OpenAI released a Chrome extension for Codex that enables the agent to work with apps and websites in the browser, operating in parallel across tabs in the background. Users retain control over which websites Codex can access. The extension extends Codex's agentic capabilities into the browser environment without requiring the user to cede control of their browsing session.
OpenAI retires GPT-5.2 models from ChatGPT, migrating users to GPT-5.5
As of June 12, 2026, OpenAI has removed GPT-5.2 Instant, GPT-5.2 Thinking, and GPT-5.2 Pro from ChatGPT, with existing conversations automatically continuing on corresponding GPT-5.5 models. The retirement follows OpenAI's stated policy of keeping models available for approximately 90 days after a successor is released. This reflects OpenAI's ongoing model lifecycle management as the GPT-5.x generation matures.
OpenAI retires GPT-5.1 models from ChatGPT, migrates users to GPT-5.3/5.4
OpenAI removed GPT-5.1 Instant, GPT-5.1 Thinking, and GPT-5.1 Pro from ChatGPT as of March 11, 2026. Existing conversations using GPT-5.1 variants are automatically migrated to corresponding current models: GPT-5.3 Instant, GPT-5.4 Thinking, and GPT-5.4 Pro. This is a routine model lifecycle action reflecting OpenAI's cadence of deprecating older model versions as newer ones become the standard.