Names, versions and owners change fast. Checked October 2026.
In plain words
Grok is both a chatbot and the large language models behind it. It was launched in November 2023 by xAI, an AI company founded by Elon Musk. You can use it in its own app or website, and directly inside X, the social network formerly called Twitter.
Its link to X is what makes it different. People can tag Grok in a public thread and ask it to explain or check a post, and it replies in the thread. It can draw on recent posts on X and on the web when it answers.
The company around it has changed shape more than once, through mergers between companies led by Elon Musk. The box above shows who makes Grok now and which model is newest.
Everyday example
Asking the one well-read friend in a group chat
In a busy group chat, someone forwards a dramatic claim. A cousin who reads everything gets tagged: "Is this true?" They scroll back, check a few links, and reply right there in the chat for everyone to see. Grok plays that role on X: tagged in a public thread, it reads related posts and pages and answers in public.
Where the example breaks: A trusted cousin weighs sources with judgement. Grok predicts a likely answer from patterns and whatever it pulls in, so it can repeat errors from the posts it reads.
Latestas of October 2026
- Made by
- SpaceX, which acquired xAI on 2 February 2026; its AI unit is called SpaceXAI
- Newest model
- Grok 4.7, released 21 September 2026, which SpaceX calls its most capable model; also offered in Cursor
These details change often. The rest of this page explains what it is, which stays true.
How it actually works
Grok is built like other modern chatbots, with live access to X as its distinctive input.
A large language model
Each Grok model is a transformer-based language model trained on a large body of text, then tuned to follow instructions and hold a conversation.
Live search of X and the web
When a question needs current facts, Grok searches posts on X and web pages, then writes an answer from what it found. This is a form of retrieval-augmented generation.
Instructions set its behaviour
A hidden system prompt tells Grok how to behave. In May 2025 xAI said an unauthorised change to that prompt caused unprompted replies about South Africa, and it began publishing Grok's system prompts on GitHub.
Pictures and video too
Grok Imagine, launched in July 2025, makes short animated clips with sound from a text prompt, and Grok can also make still images, so it is a multimodal tool.
- Created by
- xAI, founded by Elon Musk in 2023
- Launched
- November 2023, first for paying X subscribers
- Name
- From the verb "grok", coined by Robert A. Heinlein in 1961
- Open weights
- xAI released the weights of the original Grok-1 in March 2024
Like every chatbot, its answers can be wrong and should be checked against reliable sources. See hallucination and guardrails.
Questions people ask
Who owns Grok?
Grok was built by xAI, Elon Musk's AI company. xAI merged with X in March 2025, and SpaceX acquired xAI on 2 February 2026. The box above shows the current owner; the chatbot has kept the name Grok throughout.
Is Grok the same as ChatGPT?
Can you use Grok without X?
Yes. Grok has its own website and phone apps, released from December 2024 into early 2025, as well as being built into X. It has also been added to some Tesla cars.
What does Grok mean?
"Grok" is a verb coined by science fiction writer Robert A. Heinlein in his 1961 novel Stranger in a Strange Land. It means to understand something so deeply that it becomes part of you.