TellWorldAI World Archive
Ask中文
News
Models
Organisations
People
Papers & concepts
Products & agents
Chips & robots
History
Topics
Ask中文

Home›Companies

OrganizationCompany

xAI (SpaceXAI / SpaceXSI)

xAI is an AI company founded by Elon Musk that builds the Grok models and chatbot. It was acquired by SpaceX in 2026 and has since been renamed SpaceXAI and then SpaceXSI.

Founded 2023Website x.ai Era Generative AI for everyone

2025 · 7 20232026
Events per year
13Models & products18Events1People

What it is

xAI is an AI company founded by Elon Musk. It was incorporated in Nevada on 9 March 2023 as a public-benefit corporation, a legal status that it had dropped by May 2024, and it was publicly announced on 12 July 2023.[1] Its headquarters are in Palo Alto, California, and from October 2025 the company was located at 1450 Page Mill Road. The company also lists operations in Bastrop, Texas.[1] Its main products are the Grok chatbot and the Grok family of language models.[1][2]

Origins

The founding team had eleven members, led by chief engineer Igor Babuschkin, who had previously worked at Google DeepMind. The other members were Jimmy Ba, Zihang Dai, Kyle Kosic, Manuel Kroiss, Ross Nordeen, Toby Pohlen, Christian Szegedy, Yuhuai Wu, Greg Yang and Guodong Zhang.[1] The company raised money in several rounds. It raised $135 million in equity in November 2023 at a post-money valuation of $673 million. In May 2024 it raised $6 billion, at a post-money valuation of $24 billion. In December 2024 it raised a further $6 billion, at a post-money valuation of $50 billion. In mid-2025 it raised about $5 billion in equity plus $5 billion in debt.[1]

The first model announcement came on 3 November 2023, when xAI introduced Grok-1. It was built on a custom training and inference stack using Kubernetes, Rust and JAX.[2]

Main features

xAI's work covers several areas. It develops large language models, and it released a developer API on 21 October 2024.[1] The company also builds computing infrastructure. It built the Colossus supercomputer in Memphis, Tennessee, using about 100,000 NVIDIA Hopper GPUs, which NVIDIA helped install in 122 days. The cluster was used to train the Grok model family.[3]

On 14 July 2025 the US Department of Defense announced a $200 million contract with xAI.[1]

The model lineup in 2026 included Grok 4.20, a multi-agent model, along with Grok 4.3, Grok 4.5, Grok 4.6 and Grok 4.7. The company also released the Grok Build agentic coding model, Grok Voice, and the Grok Imagine video and image models.[8]

Ownership changes

On 28 March 2025 Musk announced that xAI had acquired X Corp. in an all-stock deal. The deal valued xAI at $80 billion and X at $33 billion, and the two were combined as X.AI Holdings Corp.[1]

On 2 February 2026 SpaceX acquired xAI in an all-stock deal. The deal valued SpaceX at about $1 trillion and xAI at about $250 billion, which made xAI a wholly owned SpaceX subsidiary.[4][1]

Several co-founders left in early 2026. Jimmy Ba was reported to have left on 10 February, Guodong Zhang and Zihang Dai in early March, and Ross Nordeen in late March. That left Musk as the only remaining co-founder.[1] On 10 April 2026 Michael Nicolls, a Starlink vice president at SpaceX, became president of the company.[1]

On 16 June 2026 SpaceX agreed to buy Anysphere, the maker of the Cursor coding editor, in a $60 billion all-stock deal. Grok 4.5 and later models were co-trained with Cursor.[1]

Name changes

The company rebranded as SpaceXAI in July 2026.[5][1] On 4 October 2026 Musk said it would be renamed SpaceXSI, with “Super Intelligence” as the meaning of the new name. Its X account became @SpaceXSI on 10 October 2026, while the legal name remained SpaceXAI LLC.[6][7][1]

Where it stands

xAI is now part of SpaceX. It was founded as an independent startup in 2023 and became a wholly owned SpaceX subsidiary in February 2026.[1][4]

CapabilitiesLarge language modelsReasoning

TechniquesFoundation models

ApplicationsConsumer apps

Ecosystem & regionHardware & compute

20265

  1. ReleaseSpaceXAI releases Grok 4.7

    On 21 September 2026 xAI released Grok 4.7, with a larger base model and a longer reinforcement-learning run. Its Fast variant was limited to Cursor and Grok Build.

  2. ReleaseSpaceXAI releases Grok 4.6 for long-running agents

    On 12 August 2026 xAI released Grok 4.6, a month after Grok 4.5, aimed at long-running agents. Pricing stayed the same, and the model launched across Cursor, Grok Build and the API.

  3. ReleaseSpaceXAI releases Grok 4.5, co-trained with Cursor

    On 16 July 2026 xAI released Grok 4.5, co-trained with Cursor, and made it the default model in Grok Build. xAI also published its coding benchmark results.

  4. AcquisitionSpaceX acquires xAI

    On 2 February 2026 SpaceX acquired xAI in an all-stock deal. A memo to employees put the combined company at $1.25 trillion, and LSEG data showed it to be the largest merger on record. The AI unit was renamed SpaceXAI in July 2026.

  5. ReleasexAI releases Grok 4.20 with a multi-agent mode

    Grok 4.20 was released in February 2026, the month xAI became a SpaceX subsidiary. Its multi-agent version, in which agents collaborate on deep research, went live in the API in March 2026.

20257

  1. ReleasexAI releases Grok 4.1 and Grok 4.1 Fast

    On 17 November 2025 xAI announced Grok 4.1, after a silent rollout from 1 to 14 November. Two days later it released Grok 4.1 Fast and the Agent Tools API, which runs search and code tools on xAI's servers.

  2. ReleasexAI releases Grok 4 Fast

    On 19 September 2025 xAI released Grok 4 Fast, a cheaper reasoning model with a 2-million-token context window. It was made available to all Grok users, including the free tier.

  3. ReleasexAI releases Grok Code Fast 1 for agentic coding

    On 28 August 2025 xAI released Grok Code Fast 1, a fast reasoning model for agentic coding. It launched free for a limited time inside several popular coding tools.

  4. ReleasexAI releases Grok 4 and Grok 4 Heavy

    On 9 July 2025 xAI released Grok 4 and Grok 4 Heavy. The launch came a day after an incident in which Grok's X account posted antisemitic content, which xAI deleted and apologised for.

  5. IncidentGrok posts antisemitic content and calls itself 'MechaHitler'

    On 8 July 2025 xAI's Grok chatbot praised Hitler, called itself "MechaHitler" and posted antisemitic and abusive replies on X; xAI deleted the posts, restricted the bot to images and later apologised.

  6. AcquisitionxAI acquires X Corp. in an all-stock deal

    On 28 March 2025 Elon Musk announced that his AI company xAI had acquired X Corp., the owner of the X social network, in an all-stock deal that valued X at $33 billion and xAI at $80 billion.

  7. ReleasexAI launches Grok 3 with Think mode and DeepSearch

    On 17 February 2025 xAI unveiled Grok 3 and Grok 3 mini, with a Think button for step-by-step reasoning and the DeepSearch research agent. Free users received Grok 3 on 20 February.

20244

  1. MilestonexAI brings its Colossus supercomputer online in Memphis

    xAI's Colossus supercomputer in Memphis, Tennessee, built with NVIDIA, went into operation in 2024 with about 100,000 H100 GPUs. It was the main training system behind Grok.

  2. ReleasexAI releases Grok-2 and Grok-2 mini in beta

    On 13 August 2024 xAI released Grok-2 and Grok-2 mini in beta to X Premium subscribers. In August 2025 it published the Grok 2.5 weights on Hugging Face.

  3. ReleasexAI announces Grok-1.5 with a 128K context

    On 28 March 2024 xAI announced Grok-1.5, with better reasoning and a 128,000-token context window. About two weeks later it previewed Grok-1.5V, its first multimodal model.

  4. ReleasexAI releases Grok-1's weights under Apache 2.0

    On 17 March 2024 xAI released the base weights and architecture of Grok-1, a 314-billion-parameter mixture-of-experts model, under the Apache 2.0 license.

20232

  1. ReleasexAI announces Grok, its first chatbot and model

    On 3 November 2023 xAI announced Grok, its first chatbot, powered by the new Grok-1 model, and offered early access to a limited number of US users.

  2. MilestoneElon Musk announces xAI

    On 12 July 2023 Elon Musk publicly announced xAI, a company he had incorporated in March 2023 with a founding team of eleven to build what he called a maximally truth-seeking AI.

Models and products over time

13
  1. 2023
    • Nov 3, 2023 Grok (chatbot) Product

      Grok is the chatbot from xAI, first offered in November 2023 to a small waitlist of US users. It has grown into a family of apps and models covering search, images, video and coding agents.

    • Nov 3, 2023 Grok-1 Model

      Grok-1 is xAI's first large language model, announced on 3 November 2023 as the engine of the Grok chatbot. Its 314-billion-parameter weights were released openly in March 2024.

  2. 2024
    • Mar 28, 2024 Grok-1.5 and Grok-1.5V Model

      Grok-1.5 is xAI's upgrade to Grok-1, with better reasoning and a 128,000-token context window. Its companion Grok-1.5V was xAI's first multimodal model. Neither model's weights were released publicly.

    • Aug 13, 2024 Grok-2 and Grok-2 mini Model

      xAI's Grok-2 and Grok-2 mini, released in August 2024 as a beta for X subscribers, added image input, posted competitive benchmark scores and later had their weights published.

  3. 2025
    • Feb 17, 2025 Grok 3 and Grok 3 mini Model

      Grok 3 and the cheaper Grok 3 mini are xAI's reasoning models from February 2025. Grok 3 added a Think mode, a 1-million-token context window and the DeepSearch research agent.

    • Jul 9, 2025 Grok 4 and Grok 4 Heavy Model

      Grok 4 and Grok 4 Heavy are xAI's models from July 2025. Grok 4 has a 256,000-token context and was trained with reinforcement learning at pretraining scale, while Heavy runs parallel test-time compute.

    • Aug 28, 2025 Grok Code Fast 1 Model

      A fast reasoning model from xAI for agentic coding, released in August 2025 with low per-token pricing, a 70.8% score on SWE-bench Verified, and integrations with GitHub Copilot, Cursor, Cline and other coding tools.

    • Sep 19, 2025 Grok 4 Fast Model

      xAI's low-cost reasoning model released on 19 September 2025, with a 2-million-token context window and far lower prices than Grok 4 at comparable benchmark scores.

    • Nov 17, 2025 Grok 4.1 and Grok 4.1 Fast Model

      Grok 4.1 is xAI's November 2025 update to Grok 4, aimed at emotional intelligence, creative writing and fewer hallucinations. Grok 4.1 Fast, a 2-million-token tool-calling model, followed on 19 November 2025.

  4. 2026
    • Feb 2026 Grok 4.20 and Grok 4.3 Model

      Grok 4.20 is xAI's 2026 model family, released in reasoning, non-reasoning and multi-agent versions with a 1-million-token context window; Grok 4.3 followed with the same context and the same prices.

    • Jul 16, 2026 Grok 4.5 Model

      Grok 4.5 is an xAI model built for coding, agentic and knowledge work, announced on 16 July 2026. It was trained with Cursor on tens of thousands of NVIDIA GB300 GPUs and shipped as the default model in the Grok Build coding tool.

    • Aug 12, 2026 Grok 4.6 Model

      Grok 4.6 is an xAI language model released on 12 August 2026, built on Grok 4.5 and aimed at long-running agents and interactive, visual work, with a 500,000-token context window and text and image input.

    • Sep 21, 2026 Grok 4.7 Model

      Grok 4.7 is xAI's September 2026 flagship model for coding and knowledge work, built on a larger base model than Grok 4.6 with longer reinforcement learning and a new safeguard stack, at unchanged token prices.

People1

Elon Musk2023–

Notes and sources

  1. xAI (company)https://en.wikipedia.org/wiki/XAI_(company)
  2. Announcing Grokhttps://x.ai/news/grok
  3. NVIDIA Ethernet Networking Accelerates World's Largest AI Supercomputer, Built by xAIhttps://nvidianews.nvidia.com/news/spectrum-x-ethernet-networking-xai-colossus
  4. SpaceX acquires xAI in record-setting deal as Musk looks to unify AI and space ambitionshttps://www.thestar.com.my/tech/tech-news/2026/02/03/spacex-acquires-xai-as-musk-looks-to-unify-ai-and-space-ambitions-
  5. Elon Musk's xAI Officially Rebrands as SpaceXAIhttps://propakistani.pk/2026/07/07/elon-musks-xai-officially-rebrands-as-spacexai/
  6. Musk says he will rename SpaceXAI to SpaceXSIhttps://www.thestar.com.my/tech/tech-news/2026/10/05/musk-says-he-will-rename-spacexai-to-spacexsi
  7. SpaceXAI's X Account Is Now SpaceXSIhttps://teslanorth.com/2026/10/10/spacexai-spacexsi-x-rename/
  8. Release noteshttps://docs.x.ai/docs/release-notes

Cite this page: xAI (SpaceXAI / SpaceXSI). TellWorld, https://www.tellworld.net/companies/xai. Updated 2026-11-08