GiveWell's Cost-Effectiveness Analyses

Updated: December 2022

Our cost-effectiveness analyses are the single most important input into our charity recommendations. We view cost-effectiveness analyses as valuable for helping us identify large differences in the cost-effectiveness of grants we're considering for funding and to encourage staff to think through relevant issues related to charities' work. However, although we spend significant staff time on our cost-effectiveness analyses, we consider our cost-effectiveness numbers to be extremely rough. We do not make charity recommendations solely on the basis of cost-effectiveness calculations and will rely heavily on other factors, such as an organization's track record, when we are comparing organizations with cost-effectiveness estimates that are not very different.

The model relies on philosophical values—for example, how to weigh increasing a person's income relative to averting a death—and difficult judgment calls about which we have limited information, such as the likelihood that a program as it is implemented will have the same impact as the program when it was studied. We encourage those who are interested to make a copy of the model and edit it to account for their own values. We also strongly encourage those who use our research to read more about our approach to cost-effectiveness and our page with details on a 2019 survey of about 2,000 people living in extreme poverty in Kenya and Ghana about how they value different outcomes.

Our Cost-Effectiveness Model

Last Updated: August 4, 2022

We updated our criteria and list of top charities in August 2022. You can read more about this decision here. Please note that the following model temporarily includes information on past top charities; we plan to update this in a forthcoming version. Our model can be accessed via the links below.

An extensive document about our cost-effectiveness analysis, primarily intended for staff members at GiveWell, is publicly accessible here.

Past Cost-Effectiveness Analyses

2022 Cost-Effectiveness Analyses

Version 4 — Published April 12, 2022

Version 3 — Published March 31, 2022

Version 2 — Published March 29, 2022

Version 1 — Published March 24, 2022

2021 Cost-Effectiveness Analyses

Version 3 — Published September 28, 2021

Version 2 — Published July 6, 2021

Version 1 — Published May 5, 2021

2020 Cost-Effectiveness Analyses

Version 2 — Published November 19, 2020

Version 1 — Published September 11, 2020

2019 Cost-Effectiveness Analyses

We published several updates to our model in 2019. The most recent version of the 2019 model can be accessed via the links below. Earlier versions of the 2019 model are accessible via links in the changelog.

2018 Cost-Effectiveness Analyses

In 2018, we published frequent updates to our model. The most recent version of the 2018 model can be accessed via the links below. Earlier versions of the 2018 model are accessible via links in the changelog.

2017 Cost-Effectiveness Analyses

Version 5 — Published November 27, 2017

Version 4 — Published November 8, 2017

Version 3 — Published October 27, 2017

Version 2 — Published August 16, 2017

Version 1 — Published May 20, 2017

2016 Cost-Effectiveness Analyses

Final Analysis

  • Long-lasting insecticide-treated nets, deworming, cash transfers, and seasonal malaria chemoprevention – view or make an editable copy

Mid-year update

  • Long-lasting insecticide-treated nets, deworming, cash transfers, and iodine fortification – download file (.xlsx)

2015 Cost-Effectiveness Analyses

Final Analyses

2014 Cost-Effectiveness Analyses

Final Analyses

Interim Analyses

2013 Cost-Effectiveness Analyses

2012 Cost-Effectiveness Analyses

See also this blog post discussing our 2012 cost-effectiveness estimates.

How We Use Cost-Effectiveness Estimates in Our Grantmaking

We use GiveDirectly's unconditional cash transfers as a benchmark for comparing the cost-effectiveness of different funding opportunities, which we describe in multiples of "cash." Thus, if we estimate that a funding opportunity is "10x cash," this means we estimate it to be ten times as cost-effective as unconditional cash transfers.

Note that our cost-effectiveness analyses are simplified models that do not take into account a number of factors. There are limitations to this kind of cost-effectiveness analysis, and we believe that cost-effectiveness estimates such as these should not be taken literally due to the significant uncertainty around them. We provide these estimates (a) for comparative purposes to other grants we have made or considered making, and (b) because working on them helps us ensure that we are thinking through as many of the relevant issues as possible.

We maintain a minimum cost-effectiveness threshold, or bar, that helps us decide whether to direct funding to a program. For example, we may aim to limit our grantmaking in a given period of time to grants that we estimate are at least 10x cash. This threshold changes periodically. One of the factors that can cause us to update the threshold is the amount of funding that we expect to have available for granting in a given year. When we anticipate having more funding, the cost-effectiveness bar goes down, because we expect to be able to fund more opportunities overall, including ones that are comparatively less cost-effective. When we project having less funding, the bar goes up, because we're constraining our grantmaking to the very most cost-effective opportunities.

Our process for estimating cost-effectiveness focuses on determining whether a program is cost-effective enough to consider funding (that is, whether it is above our cost-effectiveness bar); it isn't primarily intended to differentiate between values that are above that threshold.