Grok (chatbot)
Grok is a generative artificial intelligence chatbot developed by xAI. It was launched in November 2023 by Elon Musk as an initiative based on the large language model of the same name. Grok has apps for iOS and Android and is integrated with Twitter and Tesla's Optimus robot. The chatbot is named after the verb grok, coined by American author Robert A. Heinlein to describe a form of understanding.
The bot has generated various controversial responses, including conspiracy theories, praise of Adolf Hitler, antisemitism, and creating nonconsensual, sexualized images of undressed women and children. It has also referred to Musk's views when asked about controversial topics or difficult decisions. Updates since 2023 have shifted the bot politically rightward to provide conservative responses to user queries.
Background
OpenAI
Musk was one of the 11 co-founders of OpenAI, and initially co-chaired it with Sam Altman. He left the company's board in 2018, saying of his decision that he "didn't agree with some of what OpenAI team wanted to do". OpenAI went on to launch ChatGPT in the end of 2022, and GPT-4 in March 2023. The same month, Musk was one of the individuals to sign the "Pause Giant AI Experiments: An Open Letter" from the Future of Life Institute, which called for a six-month pause in the development of any AI software more powerful than GPT-4.TruthGPT
In April 2023, Musk said in an interview on Tucker Carlson Tonight that he intended to develop an AI chatbot called "TruthGPT", which he described as "a maximum truth-seeking AI that tries to understand the nature of the universe". He expressed concern to Carlson that ChatGPT was being "trained to be politically correct".Grok
TruthGPT would later be renamed after grok, a verb coined by American author Robert A. Heinlein in his 1961 science fiction novel Stranger in a Strange Land to describe a deeper than human form of understanding.History
Grok-1
In November 2023, xAI began previewing Grok as a chatbot to select users, with participation in the early access program being limited to paid X Premium users. It was announced that once the bot was out of early beta, it would only be available to higher tier X Premium+ subscribers. At the time of the preview, xAI described the chatbot as "a very early beta product – the best we could do with 2 months of training" that could "improve rapidly with each passing week".On March 11, 2024, Musk posted on X that the language model would go open source within a week. Six days later, on March 17, Grok-1 was open sourced under the Apache-2.0 license. Disclosed were the network's architecture and its weight parameters. On March 26, 2024, Musk announced that Grok would be enabled for X Premium subscribers, in addition to those on Premium+.
Grok-1.5
On March 29, 2024, Grok-1.5 was announced, with "improved reasoning capabilities" and a context length of 128,000 tokens. Grok-1.5 was released to all X Premium users on May 15, 2024. On April 4, 2024, an update to X's "Explore" page included summaries of breaking news stories written by Grok, a task previously assigned to a human curation team.On April 12, 2024, Grok-1.5 Vision was announced, which xAI claimed could "process a wide variety of visual information, including documents, diagrams, graphs, screenshots, and photographs." However, Grok-1.5V was never released to the public. On May 4, 2024, Grok became available in the United Kingdom, which was the only European country to support it at the time due to the impending Artificial Intelligence Act rules in the European Union. Grok was later reviewed by the EU and was released on May 16, 2024.
Grok-2
On August 14, 2024, Grok-2 and Grok-2 mini were announced, with upgraded performance and reasoning, and image generation capability using Flux by Black Forest Labs. Grok-2 mini was described as a "small but capable sibling" of Grok-2 that "offers a balance between speed and answer quality" and was released on the same day as the announcement. Grok-2 was released six days later, on August 20. On October 28, 2024, Grok received image understanding capabilities. On November 16, 2024, Grok received web search capabilities. On November 23, 2024, Grok received PDF understanding capabilities.On December 6, 2024, Grok was enabled for free users, but with usage limits. On December 9, 2024, Grok received [|Aurora], a new text-to-image model developed by xAI. Also in December 2024, xAI released standalone Grok web and iOS apps, in addition to its existing availability on X. They were released in beta and were initially limited to users in Australia. The app was made available to users worldwide on January 9, 2025.
On January 2, 2025, xAI updated the Grok logo. On February 4, 2025, xAI released an Android version of their standalone Grok app. The release was firstly limited to Australia, Canada, India, Saudi Arabia and the Philippines and later released worldwide. In August 2025, Grok 2.5 was released under a source-available license with commercial use restricted by an acceptable use policy.
Grok 3
On February 17, 2025, xAI released its flagship AI model, Grok 3, along with other updates to Grok. Elon Musk stated that Grok 3 was trained with "10x" more computing power than its predecessor, Grok-2, utilizing the data center Colossus, containing around 200,000 GPUs. The model was trained on an expanded dataset that reportedly included legal filings, with xAI claiming it outperformed OpenAI's GPT-4o on benchmarks such as AIME for mathematical reasoning and GPQA for PhD-level science problems. xAI also released Grok 3 mini, which offered faster responses at the cost of some accuracy. Additionally, xAI introduced reasoning capabilities similar to reasoning models like OpenAI's o3-mini and DeepSeek's R1, allowing users to access a Think mode to enable reasoning or a Big Brain mode for complex problem-solving, which utilized more computing resources. The 'Big Brain' mode was never made publicly available.xAI claimed that Grok 3 Reasoning surpassed the best version of OpenAI's o3-mini, o3-mini-high, on several popular benchmarks, including a newer mathematics benchmark called AIME 2025 based on problems from the American Invitational Mathematics Examination 2025 exam. An OpenAI employee criticized xAI's published comparison graph, pointing out that it included the Grok 3 results using the "consensus@64" technique, and only showed the o3-mini-high results without this technique. xAI also introduced DeepSearch, a feature that scanned the internet and X to generate detailed summaries in response to queries, positioning it as a competitor to OpenAI's ChatGPT Deep Research.
Initially, access to Grok 3 was limited to X's Premium+ and xAI's SuperGrok subscribers, with plans to offer it later via xAI's enterprise API. Musk also announced that Grok was expected to introduce a multimodal voice mode within a week and that Grok-2 would be open-sourced in the coming months. Hours after the announcement, X raised the price of its Premium+ subscription to $40.00 per month, up from $22.00. Grok 3 was made available to free users on February 20, 2025, for a "short time". This access was never disabled, despite being initially described as temporary. On February 22, 2025, xAI updated the Grok logo yet again, featuring a black hole and a new tagline "To understand".
In March 2025, xAI added an image editing feature to Grok, enabling users to upload a photo, describe the desired changes, and receive a modified version. Alongside this, xAI released DeeperSearch, an enhanced version of DeepSearch that utilizes extended search and more reasoning. In April 2025, xAI launched an API for Grok 3. It costs $3 per million input tokens and $15 per million generated tokens. In May 2025, Grok 3 was announced for Microsoft Azure. In July 2025 Musk announced that Grok had been "significantly improved" and noted that users would "notice a difference". When the chatbot was found to be posting antisemitic content and praising Hitler, days later, some of these changes were reversed.
Grok 4
On July 9, 2025, xAI released Grok 4 and 4 Heavy, along with other updates to Grok. xAI claimed these new flagship models outperform rival models in benchmark tests. Within a week of Grok 4's release, it was demonstrated to occasionally research Elon Musk's views before providing its answer to a query; a request for Grok to discuss the Middle East conflict led to Grok declaring that it was "looking" at Musk's views "to see if they guide the answer", as "Elon Musk's stance could provide context, given his influence". In July 2025, anime-themed avatars called "Companions" were added. On August 10, 2025, unlimited access to Grok 4 for free users was made available for a limited time to compete with OpenAI's GPT-5. However, free users are restricted to two prompts every two hours.Grok 4 Fast
To appeal to enterprise customers, xAI released Grok 4 Fast in September 2025. Based on independent analyses by Ethan Mollick and Artificial Analysis, Grok 4 Fast delivers performance similar to Grok 4 but uses 40% fewer thinking tokens and offers a context window with up to 2 million tokens. Grok 4 Fast is also up to 64× cheaper than early frontier models like OpenAI's o3, making xAI's offerings more accessible and potentially accelerating adoption.Grok Code Fast 1
On August 28, 2025, xAI released Grok Code Fast 1, a speedy and economical reasoning model that excels at agentic coding. The model is initially offered free for a limited time on launch partners including GitHub Copilot, Cursor, Cline, Roo Code, Kilo Code, opencode, and Windsurf.Grok 4.1
On November 17, 2025, xAI released Grok 4.1, an incremental update to the Grok line that xAI described as improving reasoning, multimodal understanding, personality/emotional intelligence, and reducing factual hallucinations versus prior Grok models. The release followed a two-week silent rollout during which xAI reported blind pairwise evaluations on live traffic and used feedback to refine the model's behavior.xAI simultaneously announced Grok 4.1 Fast, an optimized variant aimed at tool-calling and agentic workflows that it said supports a 2-million-token context window and an Agent Tools API for orchestrating external tools.
Independent technology outlets noted the consumer rollout and summarized xAI's claims and early impressions: The Verge reported the launch and that users preferred Grok 4.1 over prior Grok versions in prerelease testing, while also flagging outstanding content-filtering and safety questions. Gizmodos early hands-on described Grok 4.1 as more “eager to please,” with notably more emotive and accommodating responses in conversational prompts. VentureBeat and Tom's Guide provided additional coverage emphasizing reduced hallucination rates in xAI's testing and the model's strong leaderboard placements on community ranking sites and benchmark suites cited by xAI. Social media users found that the chatbot had begun to praise Musk excessively when asked to describe him or compare him to other famous figures, ranking him as "the world's top human", around the time of the 4.1 update.
xAI published benchmarking and methodology details in the announcement and linked model card ; independent coverage treated those claims as significant but emphasized that many metrics derive from xAI's internal evaluations or community leaderboards rather than peer-reviewed third-party benchmarks.