LangChain makes developer tooling for building applications on top of large language models, including an open-source framework for chaining prompts, tools, and memory into more complex AI workflows. The company was founded in 2022 by Harrison Chase, who serves as CEO, and Ankush Gola.
LangChain joined the unicorn tier in October 2025 after raising a $125 million Series B at a $1.3 billion valuation, bringing its total funding to roughly $260 million since a 2023 seed round led by Benchmark. Sequoia Capital led the company's 2024 Series A.