Elon Musk’s Frontier AI Lab
xAI is the world's third-most valuable AI startup and Elon Musk's personal frontier AI lab. It is already playing a load-bearing role in the future success of Musk's other companies.
Since its founding in early 2023, the U.S. artificial intelligence company xAI has rapidly become one of the world’s leading AI labs and one of the world’s most valuable privately-owned companies. After its most recent January 2026 fundraising round, xAI is believed to be valued at more than $230 billion, making it the third-most valuable private AI lab after OpenAI and Anthropic.1 Headquartered in Palo Alto, California, xAI’s core staff as of 2025 numbered roughly 300 people.2 Founded by Tesla, SpaceX, and OpenAI founder Elon Musk, who is currently 54 years old, xAI merged with X (formerly Twitter) in March 2025, resulting in a combined corporation that is approximately 59% owned by Musk personally.3 In Musk’s own words, the mission of xAI is to “understand the true nature of the universe,” and the company plays an increasingly prominent role in Musk’s constellation of companies.4