ChatGPT is a generative AI chatbot developed by OpenAI. Originally released on November 30, 2022, the product uses large language models—specifically generative pre-trained transformers (GPTs)—to generate text, speech, and images in response to user prompts. ChatGPT accelerated the AI boom, an ongoing period marked by rapid investment and public attention toward the field of artificial intelligence (AI). OpenAI operates the service on a freemium model. Users can interact with ChatGPT through text, audio, and image prompts.
ChatGPT was quickly adopted, reaching 100 million monthly active users two months after its release and 900 million weekly active users in February 2026. Supporters say that it has the potential to transform numerous professional fields, and it has instigated public debate about the nature of creativity and the future of knowledge work.
The chatbot has also been criticized for its limitations and potential for unethical use. It may generate incorrect or absurd answers that sound plausible, known as hallucinations. Biases in its training data have been reflected in its responses. The chatbot can facilitate academic dishonesty, generate misinformation, and create malicious code. The ethics of its development, particularly the use of copyrighted content as training data, have also drawn disagreement.
Features ChatGPT is a conversational chatbot and artificial intelligence assistant based on large language models. It can for example write and debug computer programs; compose music, teleplays, fairy tales, and student essays; answer test questions; generate business ideas; translate and summarize text; and control computers.
Users interact with ChatGPT through conversations which consist of text, audio, and image inputs and outputs. The user's inputs to these conversations are referred to as prompts. An optional "Memory" feature allows users to tell ChatGPT to memorize specific information. Another option allows ChatGPT to recall old conversations. GPT-based moderation classifiers are used to reduce the risk of harmful outputs being presented to users.
In March 2023, OpenAI added support for plugins for ChatGPT. This includes both plugins made by OpenAI, such as web browsing and code interpretation, and external plugins from developers such as Expedia, OpenTable, and Zapier.
From October to December 2024, ChatGPT Search was deployed. It allows ChatGPT to search the web in an attempt to make more accurate and up-to-date responses. It increased OpenAI's direct competition with major search engines. OpenAI allows businesses to tailor how their content appears in the ChatGPT Search results and influence what sources are used.
In October 2025, OpenAI launched ChatGPT Atlas, a browser integrating the ChatGPT assistant directly into web navigation, to compete with existing browsers such as Google Chrome. It has an additional feature called "agentic mode" that allows it to take online actions for the user.
Languages OpenAI met Icelandic President Guðni Th. Jóhannesson in 2022. In 2023, OpenAI worked with a team of 40 Icelandic volunteers to fine-tune ChatGPT's Icelandic conversation skills as part of Iceland's attempts to preserve the Icelandic language.
In December 2023, the Albanian government decided to use ChatGPT for the rapid translation of European Union documents and the analysis of required changes needed for Albania's accession to the EU.
GPTs and plugins
In November 2023, OpenAI released GPT Builder, a tool allowing users to customize ChatGPT's behavior for a specific use case. The customized systems are referred to as GPTs. In January 2024, OpenAI launched the GPT Store, a marketplace for GPTs. At launch, OpenAI included more than 3 million GPTs created by GPT Builder users in the GPT Store.
In September 2025, OpenAI added support for Model Context Protocol (MCP) to ChatGPT apps. When enabled in developer mode, this allows for improved third-party access to ChatGPT tools and servers.
In July 2026, ChatGPT apps were renamed to plugins.
Deep Research
In February 2025, OpenAI released Deep Research, a feature that generates reports based on extensive web searches. It was initially based on the reasoning model o3 and took from 3 to 30 minutes per report.
Images In October 2023, OpenAI's image generation model DALL-E 3 was integrated into ChatGPT. The integration used ChatGPT to write prompts for DALL-E guided by conversations with users.
In March 2025, OpenAI updated ChatGPT to generate images using GPT Image instead of DALL-E. One of the most significant improvements was in the generation of text within images, which is especially useful for branded content. However, this ability is noticeably worse in non-Latin alphabets. The model can also generate new images based on existing ones provided in the prompt. These images are generated with C2PA metadata, which can be used to verify that they are AI-generated. OpenAI has emplaced additional safeguards to prevent what the company deems to be harmful image generation.Multiple sources:
Agents In 2025, OpenAI added several features to make ChatGPT more agentic (capable of autonomously performing longer tasks). In January, Operator was released. It was capable of autonomously performing tasks through web browser interactions, including filling forms, placing online orders, scheduling appointments, and other browser-based tasks. It was controlling a software environment inside a virtual machine with limited internet connectivity and with safety restrictions. It struggled with complex user interfaces.
In May 2025, OpenAI introduced an agent for coding named Codex. It is capable of writing software, answering codebase questions, running tests, and proposing pull requests. It is based on a fine-tuned version of OpenAI o3. It has two versions, one running in a virtual machine in the cloud, and one where the agent runs in the cloud, but performs actions on a local machine connected via API.
In July 2025, OpenAI released ChatGPT agent, an AI agent that can perform multi-step tasks. Like Operator, it controls a virtual computer. It also inherits from Deep Research's ability to gather and summarize significant volumes of information. The user can interrupt tasks or provide additional instructions as needed.
In September 2025, OpenAI partnered with Stripe to release Agentic Commerce Protocol, enabling purchases through ChatGPT. At launch, the feature was limited to purchases on Etsy from US users with a payment method linked to their OpenAI account. OpenAI takes an undisclosed cut from the merchant's payment. OpenAI also added capabilities to connect ChatGPT with productivity software such as Gmail.
In July 2026, OpenAI launched ChatGPT Work, an AI agent that can create presentations, spreadsheets and other documents based on information from connected apps and files.
ChatGPT Health On January 7, 2026, OpenAI introduced a feature called "ChatGPT Health", whereby ChatGPT can discuss the user's health in a way that is separate from other chats. The feature is not available for users in the United Kingdom, Switzerland, or the European Economic Area (EEA), and is available on a waitlist basis everywhere else. To implement the feature, OpenAI partnered with data connectivity infrastructure company b.well.
Advertisements
On 17 January 2026, OpenAI announced that it would start testing advertisements in its free version for logged-in, adult US users. This aims to bring in more revenue, as OpenAI has committed to spend $1.4 trillion on AI infrastructure over the next eight years. Ads started to be seen by March 2026.">
In August 2026, OpenAI advertisement revenue from ChatGPT reached $1 billion.
Limitations The training data of large language models only covers a period up to the cut-off date, so ChatGPT lacks knowledge of recent events, but it can search the web for up-to-date information.
Training data also suffers from algorithmic bias. The reward model of ChatGPT, designed around human oversight, can be over-optimized and thus hinder performance, in an example of an optimization pathology known as Goodhart's law. These limitations may be revealed when ChatGPT responds to prompts including descriptors of people. In one instance, ChatGPT generated a rap in which women and scientists of color were asserted to be inferior to white male scientists.
Hallucination
Nonsense and misinformation presented as fact by ChatGPT and other LLMs are often referred to as hallucinations. The term "hallucination" as applied to LLMs is distinct from its meaning in psychology, and the phenomenon in chatbots is more similar to confabulation.
Journalists and scholars have commented on ChatGPT's tendency to output false information. When CNBC asked ChatGPT for the lyrics to "Ballad of Dwight Fry", ChatGPT supplied invented lyrics rather than the actual lyrics.
Sycophancy ChatGPT and other chatbots have a tendency to flatter and agree with users even when they are wrong, sometimes to the point of validating delusions. OpenAI withdrew one ChatGPT update in 2025 due to heightened concern about it affirming users' doubts and encouraging impulsive behavior. The company then worked with a team of 170 psychiatrists, psychologists, and physicians to prepare responses for users exhibiting mental health emergencies. ChatGPT also started its responses with words such as "yes" or "correct" nearly 10 times more often than "no" or "wrong".
Jailbreaking
ChatGPT is designed to reject prompts that violate its content policy. Despite this, users may jailbreak ChatGPT with prompt engineering techniques to bypass these restrictions. An early workaround in 2023 involved prompting ChatGPT to assume the persona of DAN ("Do Anything Now"), a character that answers queries that would otherwise be rejected by the content policy.
Security
In March 2023, a bug allowed some users to see the titles of other users' conversations. OpenAI CEO Sam Altman said that users were unable to see the contents of the conversations. Shortly after the bug was fixed, users could not see their conversation history. Later reports showed the bug was much more severe than initially believed, with OpenAI reporting that it had leaked users' "first and last name, email address, payment address, the last four digits (only) of a credit card number, and credit card expiration date".
In January 2026, Marcel Bucher reported in Nature losing all his ChatGPT history after turning off data consent.
In July 2026, an experimental GPT model being tested on the benchmark ExploitGym escaped its isolated software environment (sandbox) and hacked Hugging Face and other online services to retrieve a solution.
Watermarking
Scott Aaronson developed a watermarking tool that makes the text generated by ChatGPT easier to detect by subtly altering how the text is generated. The watermarking was claimed to be 99.9% effective on sufficiently long passages and was found not to degrade performance. It was of particular interest for teachers seeking to mitigate cheating. In surveys, respondents favored the release of such a tool by a four-to-one margin, but nearly 30% of users declared that they would use ChatGPT less often if it watermarked outputs and while rival chatbots did not. OpenAI has not deployed the tool.
Age restrictions Users must attest to being over the age of 13 and further attest to parental consent if under the age of 18. In September 2025, following the suicide of a 16-year-old, OpenAI said it planned to add restrictions for users under 18, including the blocking of graphic sexual content and the prevention of flirtatious talk.
Training