ImpactMatters has been acquired by Charity Navigator.

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ImpactMatters has been acquired by Charity Navigator.

Learn more on See an example of the new impact rating

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Our mission is to guide donors to high-impact nonprofits by producing ratings of impact.

We believe strongly in the nonprofit sector as a way to improve people’s lives. Our ratings are designed to help the sector flourish by rewarding impact.

Impact analysis makes for a better nonprofit sector

Social impact is the change in outcomes caused by a social program relative to cost. Some programs are more effective than others at changing outcomes. However, this data is not available to most donors, preventing them from pinpointing the impact of their own donation. Through data analysis, ImpactMatters calculates the impact of a nonprofit’s program and issues a rating. Donors can use these ratings to make more informed decisions about their giving.

Impact analysis is important because it can highlight substantial differences in effectiveness. Consider two programs pursuing the same mission: boosting income for the poor.


$30 in additional income per $1 in program spending by the nonprofit


Nonprofit B

$0.60 in additional income per $1 in program spending by the nonprofit

TechnoServe is more than 50x as cost-effective at boosting income for people living in poverty. We believe donors and nonprofits benefit when this information is presented transparently.

How are we different?

Our ratings answer a critical question: How will a donation directly improve a life? To answer that question, we follow three simple principles:

Reward impact

We estimate the changes in outcomes, such as lives saved or income earned, that are attributed to a nonprofit’s work. We divide these changes in outcomes by costs and compare to benchmarks to rate impact. Highly rated nonprofits are making good use of a dollar to change lives.

Don’t punish overhead

We focus on what matters: impact. Focusing on financial indicators like overhead vs. program spending punishes nonprofits that spend money to be successful — and fails to identify which nonprofits are doing good.

Support nonprofits

In our experience, nonprofits want to share their impact with the public, but doing so can be a complicated and costly process. We provide tips, tools and resources to make the process easier. We believe strongly in the nonprofit sector as a way to improve people’s lives and want to see it flourish.

Our values

Head and the heart

We help donors choose the most effective organizations that advance the causes they're most passionate about.

Improve constantly

Our ratings are not perfect and we strive to improve them every day. We welcome your thoughts, suggestions and corrections.

Be accountable

We believe a strong rating agency listens to people on both sides of the rating. We routinely solicit feedback and are always eager to hear what donors and nonprofits have to say.

Elijah Goldberg

Elijah Goldberg

Executive Director

Elijah co-founded ImpactMatters with Dean Karlan. He previously co-founded and served as executive director of Walimu, a health nonprofit in Uganda. He received his B.A. in economics from Yale.

Michael M. Weinstein

Michael M. Weinstein


Michael holds a Ph.D. in economics from M.I.T. and previously served as chief program officer for the Robin Hood Foundation. During the 1990s, he served on the editorial board of The New York Times and as the Times’ economics columnist.

Tamsin Chen

Tamsin Chen

Ratings Director

Tamsin leads ImpactMatters process to rate nonprofits. She received her B.A. in International Studies and Economics from Vassar and led the Vassar Haiti Project.

Josh Twersky

Josh Twersky

Dev and Ops Manager

Josh manages fundraising, finances and human resources. He previously worked as a paralegal at Ladas and Parry L.L.P. and as an operations supervisor at SPORTLOGiQ. He received his bachelor's degree from McGill University.

Maria Winchell

Maria Winchell

Research Analyst

Maria gathers data and conducts analysis for impact reports. She received her B.A. in Economics and Political and Social Thought from University of Virginia.

Stan Pollak

Stan Pollak


Stan oversees ImpactMatters financial operations. Over a thirty year career at Citigroup, he worked as C.F.O. and Finance Director for multiple business units, most recently Strategy Sourcing and Procurement Services.

Paul Brest

Former Dean and Professor Emeritus (active) at Stanford Law School
Former President of the William and Flora Hewlett Foundation

Tamara Fox

Director of Evaluation and Learning, Strategy Unit at Open Society Foundations
Former Senior Advisor for Learning and Evaluation Strategy at the Social Science Research Council

Dean Karlan

Co-founder and Chair of the Board of ImpactMatters
Professor of Economics and Finance at Northwestern University
President and Founder of Innovations for Poverty Action

Kevin Starr

Director of the Mulago Foundation and the Rainer Arnhold Fellows Program

Michael M. Weinstein

President of ImpactMatters
Former Chief Program Officer for the Robin Hood Foundation

ImpactMatters is a 501(c)(3) nonprofit. Our employer identification number is 47-5047252.

We are a free and independent source of information. We are funded by foundations and individual donors and do not accept financial support from any nonprofits, rated or unrated.

Contact us with any questions.

GuideStar by Candid

GuideStar by Candid and ImpactMatters collaborate to increase the amount of impact information available on nonprofits. ImpactMatters uses GuideStar Platinum data as the basis of some of its ratings. GuideStar and ImpactMatters also work together to increase the number of nonprofits reporting high quality impact data through the GuideStar Platinum program.

Charity Navigator

Now in its second year of an innovative collaboration, Charity Navigator is publishing impact information prepared by charities and gathered by ImpactMatters and three other partners, GuideStar, Classy and GlobalGiving. Through this collaboration, ImpactMatters’ ratings are displayed on the charity rating pages on Charity Navigator’s site.

Interested in partnering with us? Reach out to

We do not accept any sponsorship or contribution from nonprofits for ratings.