ChatGPT

OpenAI’s general-purpose AI assistant: powered by the GPT-5.6 series, with the ChatGPT Work agent covering office tasks like site building, email, and documents; ad placements are now open.

ChatGPT is OpenAI’s general-purpose AI assistant and, since its launch in late 2022, the de facto benchmark for the category. The current flagship is the GPT-5.6 series, rolled out to all users on July 9 in three tiers—Sol (flagship), Terra (balanced), and Luna (high-speed, low-cost). Voice is driven by the new GPT-Live-1 model, which supports full-duplex conversations so you can speak while listening. ChatGPT spans five platforms—Web, iOS, Android, macOS, and Windows—with Chat, Work, and Codex now consolidated into a single unified desktop app.

The Free tier covers everyday Q&A and light writing; the $8/month Go tier is built for budget-conscious users; the $20/month Plus tier is the workhorse for personal productivity, bundling Deep Research, image generation, and Advanced Voice; and the Pro tier gives heavy users higher limits. On July 21, 2026, OpenAI officially opened ChatGPT to advertising (an official ads page plus self-serve campaigns via Ads Manager, with Best Buy, Lowe’s, and VistaPrint as the first advertisers). Ads are clearly labeled and kept separate from answers—a landmark step in leading AI assistants shifting from subscription/API revenue toward advertising. Typical uses range from research, copywriting, and coding to multi-step tasks across apps and files with the now fully available ChatGPT Work (site building, email drafting, and document handling can all be delivered end to end).

Compared with rivals like Claude and Gemini, ChatGPT’s niche lies in its user scale and ecosystem completeness: a full suite of extras—plugin directory, custom GPTs, the Sites site builder, the memory system, and the Codex coding agent—makes it closer to a platform than a single chat tool, with the richest selection of third-party integrations and tutorial resources of any assistant.

Worth noting: the Free and Go tiers now include ads in some regions; models are iterated and deprecated at a fast pace, so workflows that depend on specific model behavior should factor in migration costs; direct access from mainland China is restricted.

Model Iteration Timeline

Date	Version	Highlights
2022-11	ChatGPT (GPT-3.5)	Conversational AI debuts; 100M users in two months
2023-03	GPT-4	Multimodal input; human-level performance on professional exams
2024-05	GPT-4o	Natively omni-modal; real-time voice and vision interaction opened to free users
2024-09	o1-preview	First reasoning model; thinks before answering
2025-08	GPT-5	Unifies the reasoning and fast-response model lines
2026-04	GPT-5.5	Includes Thinking / Pro versions; stronger decision-making and planning
2026-07	GPT-5.6	Sol / Terra / Luna tiers launch together; major efficiency gains

Source: Agentopia · See /llms.txt for the full site-wide machine catalog