Perplexity AI, Inc. develops Perplexity, an AI-powered web search engine that synthesizes cited responses to user queries from real-time web content using large language models, alongside products like Perplexity Pro subscription for document search and API access, Perplexity Assistant for multi-modal tasks across apps, Comet Chromium-based AI browser, Shopping Hub for product recommendations, and finance tools for stock data and analysis. The platform serves worldwide individual and enterprise users through free public access, paid Pro and Enterprise Pro tiers supporting up to 500 internal files, and complimentary Pro subscriptions for students, U.S. military veterans, and government employees. It employs multiple LLMs including GPT-4.5, Claude 3.5 Sonnet, Gemini 1.5 Pro, and custom Sonar based on Meta's Llama model, integrated with a real-time web search engine. Co-founded in August 2022 by Aravind Srinivas (CEO, ex-OpenAI and Google DeepMind researcher), Denis Yarats, Johnny Ho, and Andy Konwinski, all engineers with AI and machine learning backgrounds. The company raised $165 million in April 2024 at over $1 billion valuation, $500 million in June 2025 at $14 billion valuation, and additional rounds in early 2026 reaching $21.21 billion valuation, backed by investors including Nvidia, Jeff Bezos, Databricks, and 1789 Capital. Headquartered in San Francisco, California, it maintains offices in Palo Alto, New York City, Austin, Washington D.C., London, Berlin, and Belgrade.