Holden Karnofsky

Holden Karnofsky is a philanthropist and co-founder of Open Philanthropy (formerly the Open Philanthropy Project), one of the largest funders of effective altruism-aligned causes. He previously co-founded GiveWell, an organization focused on evaluating charities by impact per dollar donated, which became influential in the effective altruism movement.

Karnofsky has been a central figure in shaping philanthropic strategy around global catastrophic risks, particularly artificial intelligence safety and biosecurity. His work emphasizes cause prioritization—identifying which problems offer the greatest opportunity to improve the world per unit of resources invested. Open Philanthropy, under his leadership, has distributed hundreds of millions of dollars to research and policy work in AI safety, pandemic preparedness, and other cause areas aligned with effective altruism principles.

He is recognized as a thought leader in discussions about long-term future risks and the moral weight of future generations, contributing significantly to how major philanthropic institutions approach existential risk mitigation.

Holden Karnofsky co-founded GiveWell in 2007 to improve charitable giving through rigorous impact evaluation, and later co-founded Open Philanthropy to direct large-scale philanthropic capital toward high-impact causes. He has become a central intellectual figure in effective altruism, shaping how major institutions think about global catastrophic risks, AI safety, and long-term future considerations.