What Is Grok? xAI's Chatbot and Models in 2026

Grok in a few sentences

Grok is an AI assistant you talk to in plain language. You type a question, paste a draft or attach a photo, and it writes back: an explanation, a rewrite, a plan, a piece of code, a translation. The name covers two things at once. It is the chatbot that xAI runs on grok.com, inside X and in its phone apps, and it is the family of large language models behind that chatbot, which developers can also call through an API.

The first Grok appeared in November 2023. Since then xAI has shipped a long line of models, each faster or smarter than the last, and the newest one as of October 2026 is Grok 4.7. If you only remember one thing, remember this: "Grok" is a brand for both a product and a set of models, and which model you are talking to depends on where you use it.

Grok.Online, the site you are on, is an independent free website. It is not run by xAI, SpaceX or X. Our chat sends your messages to real Grok models through a cloud API, so you can try Grok here without an account.

Who makes Grok: xAI, SpaceX and the new names

Grok was built by xAI, an AI company Elon Musk founded in March 2023 and announced that July. In March 2025 xAI combined with X Corp, the owner of the social network X, which is why Grok is woven into X so closely.

The company story changed again in 2026. On February 2, 2026, SpaceX acquired xAI, making it a wholly owned SpaceX subsidiary; xAI's own site announced it as "xAI joins SpaceX". During 2026 the company was renamed SpaceXAI, and in October 2026 it started presenting itself as SpaceXSI, short for SpaceX Super Intelligence. The legal entity is SpaceXAI LLC. You will see all of these names around the web: OpenRouter, for example, lists the models under "SpaceXAI". The developer documentation still lives at docs.x.ai and the model ids still start with grok-, so on this site we mostly keep saying xAI.

None of this changes how Grok works for you, but it explains the odd names on pricing pages and in app stores, and why Grok now appears in products such as Cursor, the code editor SpaceX bought in 2026.

How Grok works

Under the hood, Grok is a large language model: a neural network trained on a very large amount of text, code and images to predict what comes next in a piece of writing. After that broad training, xAI tunes the model with human feedback and reinforcement learning so it follows instructions, holds a conversation and refuses clearly harmful requests. When you send a message, the model reads the whole conversation so far and generates its reply one small piece (a token) at a time.

Two ideas help you understand the Grok line-up:

Reasoning. Newer Grok models can "think" before they answer. They write a hidden chain of working-out, check it, and only then give you the final reply. That makes them better at maths, logic and multi-step tasks, at the cost of a few extra seconds. Some models let you choose how much effort to spend, from none to very high. Our guide to reasoning models goes deeper.
Context window. This is how much text the model can keep in view at once, measured in tokens. Recent Grok models accept hundreds of thousands of tokens or more, enough for a long report. Whatever falls outside the window, the model simply does not see.

A Grok model on its own knows only what was in its training data, up to a cut-off date. In xAI's apps the chatbot adds tools on top, such as searching the web and X, to pull in newer facts. Without those tools, as in our chat, Grok cannot see anything that happened after its cut-off.

The Grok models that matter in 2026

xAI released more Grok models in 2026 than in any earlier year. These are the ones you are most likely to meet:

Model	Released	What it is for	In our chat
Grok 4.20	Beta in February, API on March 10, 2026	Fast everyday answers and tool use; also a multi-agent version	Yes, the default
Grok 4.3	April 30, 2026	Reasoning model for careful, accuracy-sensitive work	Yes, as Grok 4.3 Thinking
Grok 4.5	July 2026	Coding, agents and knowledge work; trained alongside Cursor	No
Grok 4.6	August 12, 2026	Longer-running agents, interactive and visual work	No
Grok 4.7	September 21, 2026	Newest flagship for code, agents and complex tasks	Yes, 10 messages a day
Grok Imagine	From August 2025	Making images and short videos	No

Older names still float around: Grok 3 from February 2025, Grok 4 from July 2025, the cheaper Grok 4 Fast and Grok 4.1 Fast, and the coding models Grok Code Fast 1 and Grok Build 0.1. The full story, with every date, is on our Grok history page.

Two early models are also available as open weights that anyone can download: Grok-1, released in March 2024 under the Apache 2.0 license, and Grok 2.5, published in August 2025 under xAI's own community license. Elon Musk said in August 2025 that Grok 3 would follow in about six months; as of October 2026 its weights have not been published. Every current Grok model is closed and runs only on xAI's servers or its partners'.

What the official Grok can do

On grok.com and in the official apps, Grok is more than a model. Depending on your plan and country, xAI's version offers:

chat with a choice of modes, from quick answers to slower, deeper ones;
searching the web and posts on X, with links to sources;
reading images and uploaded files;
voice conversations;
image and video generation through Grok Imagine;
agent features such as Grok Bot and the Grok Build coding tool on paid plans.

Grok is also built into X: you can open it from the Grok tab or ask it about a post. That close link to X is the feature people most often associate with Grok, and the main thing that sets it apart from other assistants.

Our free chat is deliberately simpler. It runs the Grok models themselves, reads images you attach, and adds tools, assistants and a prompt library, but it has no web or X search, no voice and no image generation. It answers only from what the model already knows.

What to watch out for

Grok is useful, and like every chatbot it has limits you should keep in mind:

It can be wrong with confidence. A fluent answer is not a checked answer. Verify names, numbers, quotes and anything you plan to rely on. Our guide to fact-checking AI answers shows a quick routine.
Its knowledge stops at a date. Without search, it does not know recent news. Grok 4.7, the newest model, has a knowledge cut-off of May 2026 according to xAI.
Tone. Grok was designed to be direct and sometimes witty. That suits many people, but ask for a neutral, formal style when you need one.
Controversies. Grok's posts on X and its image features have drawn heavy criticism at times, including offensive replies in July 2025 and misuse of image editing to create sexualized pictures of real people around the turn of 2026, which led to restrictions and scrutiny from regulators. Treat its output on sensitive topics with extra care.
Privacy. Do not paste passwords, ID numbers or confidential documents into any chatbot, ours included.
Not a professional. For health, legal or money decisions, use Grok to prepare questions and understand terms, then talk to a qualified person.

Where you can use Grok

You have four main options, and they suit different people:

grok.com in any browser, with a limited free tier and paid plans for more use and newer models.
Grok on X, inside the X website and apps.
The official Grok apps for iPhone and Android.
Through other sites and tools that use the API, including this one, plus the xAI API and OpenRouter if you write code.

Our Grok web guide compares the browser options step by step, Grok for free explains what costs nothing and what does not, and Grok API is the page for developers.

Grok on Grok.Online

Our chat at grok.online/chat gives you three real Grok models with no sign-up:

Grok 4.20, the default: quick replies with reasoning switched off, good for most everyday questions.
Grok 4.3 Thinking: pauses to reason first, which helps with maths, logic and planning.
Grok 4.7: the newest flagship, limited to 10 messages a day because it costs more to run.

Every visitor gets 30 free messages a day, shared with the tool pages, and the count resets daily. You can attach an image to a message, export your history or share a read-only link to a conversation. Your chat history stays in your own browser, not on our server. The site is paid for by ads shown around the content, never inside answers.

Not sure which model to pick? Start with Grok 4.20. Switch to Grok 4.3 Thinking when an answer needs careful working-out, and save Grok 4.7 for the hardest tasks. Our comparison of Grok 4.20 and Grok 4.3 has more detail, and Grok vs ChatGPT helps if you are weighing assistants.

FAQ

Is Grok made by Elon Musk?

Grok is made by xAI, the company Elon Musk founded in 2023. Since February 2026 xAI has been part of SpaceX, another Musk company, and it now uses the names SpaceXAI and SpaceXSI.

Is Grok open source?

Only two older models have public weights: Grok-1 (Apache 2.0) and Grok 2.5 (xAI's community license). The current models, including Grok 4.20, 4.3 and 4.7, are closed.

Can Grok search the internet?

The official Grok on grok.com, X and the apps can search the web and X. The Grok models in our chat cannot; they answer from training data only.

Is Grok.Online the official Grok?

No. Grok.Online is an independent website that connects to real Grok models through an API. It is not affiliated with or endorsed by xAI, SpaceX or X.

What is the newest Grok model?

Grok 4.7, released on September 21, 2026. You can try it in our chat with up to 10 messages a day.

What is Grok?