What is Grok? The AI, the word and the company behind it
Grok is the AI chatbot built into X, made by the company formerly called xAI. Here is what it does, which model is current, what the name means and how it differs from other chatbots.
Grok is an AI chatbot from SpaceXSI (formerly xAI), available in the Grok app and inside X. The latest model is Grok 4.7, released September 21, 2026. The name comes from Robert Heinlein’s 1961 novel Stranger in a Strange Land, where “grok” means to understand something completely.
What the word “grok” means
To grok something is to understand it so deeply that it becomes part of you. The word was invented by science-fiction writer Robert A. Heinlein in his 1961 novel Stranger in a Strange Land, where it is a Martian word. Merriam-Webster notes it may be the only English word that comes from Martian. It spread through computer and hacker culture, which is how an AI ended up named after it.
Grok, the AI
Grok is an AI chatbot. You can talk to it in the Grok app (iPhone, Android, web) and inside X, where it has its own tab and can be tagged in posts. It answers questions, writes and edits, explains images, searches the web and posts on X in real time, talks out loud in voice mode and makes images and short videos with Grok Imagine.
The same company also makes Grok Bot, an agent that carries out tasks for you, and Grok Build, a coding tool that runs in the terminal.
Who makes Grok
Grok was created by xAI, the AI company Elon Musk founded in March 2023. SpaceX acquired xAI in February 2026, and the company was renamed SpaceXAI in July 2026. On October 4, 2026, Musk announced another rename to SpaceXSI (“SI” for super intelligence). Official pages now use the new name in their titles, while the legal footer still says SpaceXAI LLC. Most news coverage still says xAI.
Which Grok model is current?
| Model | Released |
|---|---|
| Grok 4 (and Grok 4 Heavy) | July 9, 2025 |
| Grok 4.1 | November 17, 2025 |
| Grok 4.20 | February 2026 |
| Grok 4.3 | April 2026 |
| Grok 4.5 | July 8, 2026 |
| Grok 4.6 | August 12, 2026 |
| Grok 4.7 (latest) | September 21, 2026 |
| Grok 4.8, Grok 5 | Not released yet (see our Grok 5 tracker) |
Grok 4.7 has a 500,000-token context window, which means it can read very long documents in one go. For developers, the API price is $2 per million input tokens and $6 per million output tokens.
What makes Grok different
- It lives inside X. It can read and summarize what is happening on X right now, which most chatbots cannot do as directly.
- One bundle. Paid plans combine Grok, the Cursor coding app and X Premium perks in The X Subscription.
- An agent built in. From the $30 Premium plan up, you also get Grok Bot.
- A looser personality. Grok has fun and companion modes, and it has been more willing than rivals to joke and take edgy prompts, which has also landed it in controversy.
The controversies, briefly
Grok’s image tools were at the center of a sexual-deepfake scandal in early 2026. X limited image replies to paying users on January 9, barred editing real people into revealing clothing on January 14, and by March limited the standalone Imagine app to paid subscribers. Regulators in the UK, California, France and Ireland opened investigations. Like every chatbot, Grok can also state wrong things with confidence, so check anything important.
Questions people ask
What does grok mean?
To understand something deeply and intuitively, so completely that it becomes part of you. Heinlein coined it in 1961.
Is Grok made by Elon Musk?
Grok was created by xAI, which Elon Musk founded. xAI is now part of SpaceX and has been renamed SpaceXAI and then SpaceXSI.
Is Grok free?
There is a free tier with limited use. Paid plans start at $8 a month. See Is Grok free?
What is the newest Grok model?
Grok 4.7, released September 21, 2026. Grok 4.8 and Grok 5 have not been released.