Mercor crossed $2 billion in gross annualized revenue in June, hitting that mark just four months after reaching $1 billion.
Several AI companies are reporting revenue that is accelerating at an increasing pace. The specific metrics used to measure this growth vary across the sector. Some figures represent annualized recurring revenue, or income from paying customers before billing occurs. Others are annualized run-rate revenue, projecting twelve months of income based on the most recent month’s performance. Some refer to committed ARR, which covers signed contracts not yet onboarded. Gusto reported actual trailing 12-month revenue instead.
Despite these differences in definition, each startup listed below reports accelerating growth. This list is not exhaustive, focusing instead on companies hitting milestones at ever-faster rates.
Mercor
Brendan Foody, co-founder and CEO, announced the $2 billion milestone on Monday. The firm, which employs domain experts to train and refine AI models, reached a $500 million run rate in September.
Anthropic
Anthropic has shown revenue velocity that has captivated the entire AI sector. In late May, the company reported a revenue run rate of $47 billion. This figure was reached less than two months after the metric surpassed $30 billion.
The company reached a $9 billion revenue run rate in late 2025, up from $4 billion reported in July 2025.
Sierra
Sierra builds customer service AI agents for enterprises. After reaching its first $100 million in ARR over seven quarters, CEO Bret Taylor announced in late May that it took just two more quarters to add another $100 million.
Glean
Glean crossed $300 million in ARR in May. The seven-year-old enterprise AI startup took nine months to double its ARR from $100 million to $200 million. It then required just six months to grow that metric from $200 million to $300 million.
Gusto
The 14-year-old HR tech startup announced in May that its revenue accelerated in each of the last five quarters. Gusto was last valued at $9.3 billion in early 2022. The company reported surpassing $1 billion in trailing 12-month revenue.
This surge indicates that top-line growth is not limited to AI-native companies. Traditional firms are also seeing their growth supercharged by integrating the technology.
Clio
Clio is an 18-year-old provider of legal practice management software. Revenue took off sharply after the company embedded AI into its offering in 2023. ARR surpassed $200 million in mid-2024, doubled by late last year, and recently reached $500 million.
What it means
The speed at which these companies are scaling suggests that the initial hype cycle has settled into measurable, high-velocity performance. For the people building tools, this means the market is no longer just testing the waters; it is demanding rapid iteration and proven results. The distinction between different types of ARR matters less to investors than the sheer acceleration of the numbers.
