LMArena raises $150M Series A at $1.7B valuation

LMArena, an artificial intelligence model evaluation platform, has raised a $150 million Series A—the first significant round of venture capital financing—at a $1.7 billion post-money valuation. The funding round was led by Felicis and UC Investments.

The round also included participation from:

• Andreessen Horowitz
• The House Fund
• LDVP
• Kleiner Perkins
• Lightspeed Venture Partners
• Laude Ventures

The company has experienced rapid growth since transitioning to a commercial entity. The platform now has 5 million monthly users across 150 countries and processes 60 million conversations a month. Its consumer website lets a user type a prompt that it sends to two models, with the user then choosing which model did a better job. Those results fuel the leaderboards, which rank models on a variety of tasks including text, web development, vision, text-to-image, and other criteria. The models tested include various flavors of OpenAI GPT, Google Gemini, Anthropic Claude, and Grok, as well as ones geared toward specialties like image generation, text to image, or reasoning.

However, the startup’s rapid rise has also brought scrutiny. When LMArena started pursuing revenue, it partnered with select model companies such as OpenAI, Google, and Anthropic to make their models available for its community to evaluate. In April, a group of competitors published a paper alleging that this helped those model makers game the startup’s benchmarks, an allegation LMArena has vehemently denied.

LMArena originally launched in 2023 as Chatbot Arena, a research project built by UC Berkeley researchers Anastasios Angelopoulos and Wei-Lin Chiang, and was originally funded through grants and donations. The startup bolted out of the gate as a commercial venture with a $100 million seed round in May at a $600 million valuation. In September, it publicly launched its commercial service, AI Evaluations, in which enterprises, model labs, and developers can hire the company to perform model evaluations through its community. This gave LMArena an annualized consumption rate—which the company uses to describe its annualized recurring revenue (ARR)—of $30 million as of December, less than four months after launch. With the latest Series A, the company has raised $250 million in about seven months.

Why it matters

LMArena’s rapid valuation growth to $1.7 billion and $30 million ARR in under four months since launching its commercial service highlights the high demand for AI model evaluation tools.