Giving Multiplier was created as a research project in 2020 by Joshua Greene, a psychology professor at Harvard and Lucius Caviola, professor at University of Cambridge, who was a postdoctoral researcher at Harvard at the time. The goal of creating Giving Multiplier was to introduce people to effective charities[1][2][3] in a way that overcomes some of the psychological barriers to effective giving.[4][5] As of July 2025, Giving Multiplier has facilitated over 12,000 donations totaling more than $5.1 million from more than 5,000 donors.[6]
Giving Multiplier lets donors select their favorite charity and one of their super-effective charities (i.e., "with the heart and the head") to implement a donation bundling technique.[10] This innovation combines donors' seemingly conflicting preferences, namely, that they have their own favorite charities,[11] and they simultaneously care about effectiveness.[12] Moreover, Giving Multiplier uses donation matching to further incentivize donors to donate more effectively.[10][13] The original design by Caviola and Greene integrated donation bundling with a new technique called micro-matching.[14][10] Micro-matching works by adding matching funds on top of each donation, with a greater matching rate for a greater proportion allocated to the super-effective charity. Individual donors support the matching system to encourage others to donate, creating a "supply and demand" cycle of charitable giving.[15]
The proof of concept for Giving Multiplier was published as part of Greene and Caviola's academic research on splitting donations between favorite charities and effective charities. Their research found that including an option to split donations between a favorite charity and effective charity increased effective giving by 76%. The authors suggested that favorite-effective donation splits satisfies donors' dual motivations of supporting causes meaningful to them and effective organizations that have a big impact.[14]
Current list of super-effective charities
As of April 2025, Giving Multiplier's list of super-effective charities (based on charity evaluators' recommendations) include:
↑Kasia De Lazari Radek; Peter Singer (2025-06-18). "JOSHUA GREENE: uniting moral tribes" (Podcast). Lives Well Lived. Apple Podcasts. Retrieved 2025-11-17.
↑Dr Laurie Santos (2021-11-29). "How to Give More Effectively" (Podcast). The Happiness Lab. Apple Podcasts. Retrieved 2025-11-17.
123Schubert, Stefan; Caviola, Lucius, eds. (2024). Effective altruism and the human mind: the clash between impact and intuition. New York, NY: Oxford University Press. ISBN978-0-19-775739-0.
