ImpactMatters has been acquired by Charity Navigator.

Learn more on

ImpactMatters has been acquired by Charity Navigator.

Learn more on See an example of the new impact rating

Letter from Dean and Elijah

October 14, 2020

We are writing to share news: ImpactMatters has been acquired by Charity Navigator. Today, Charity Navigator will release a new version of its nonprofit ratings that, for the first time, incorporates impact.

When we founded ImpactMatters in 2015, our vision was to create a "market for impact", where funding flowed to nonprofits that were making the most progress on pressing issues. We met in Dean's class, "Evaluating Charitable Organizations", which was a sort of pilot for what would become ImpactMatters. The class was a cozy 22-student seminar, but Dean noted several class discussions felt more like the two of them brainstorming as peers about what is viable. When the class was over, we agreed to make the class challenge real, and start ImpactMatters.

Since then, we have experimented with different paths to achieving this vision. With our founding board member and executive director, Michael M. Weinstein, we developed our first product, the impact audit. The audit, which built off Michael's pioneering work at Robin Hood Foundation, provided a nonprofit and their funder with a rigorous estimate of mission impact, along with a rating of the quality of evidence behind the estimate and guidance for improving evaluation. While we loved working with funders and nonprofits to inform their all-important decisions, we knew that we had a larger objective, to reach millions of donors and thousands of nonprofits, and that impact audits would not get us there alone. With that in mind, in 2019 we embarked on rating nonprofits en masse by combining public data with theory and evidence from social science. In November 2019, we released over 1,000 ratings. The release, which was profiled in The New York Times (twice), was, and still is, the largest collection of publicly available impact estimates, covering $15 billion in annual nonprofit spending.

But again, we still had further to go. Ratings are only useful with an audience. From day one, we knew we either needed to build one or find one. In 2016, we had coffee with Michael Thatcher, the then-new CEO of Charity Navigator. Charity Navigator, America's largest nonprofit ratings agency, provides guidance on nonprofits' financial health and transparency to 11 million users a year. Charity Navigator has had a longstanding objective to add an assessment of impact to its ratings. We shared that hope, and over the years we collaborated, sharing data, conducting experiments and thinking about what it would take to "do impact right."

Today, we take a major step forward.

By joining forces with Charity Navigator, we are immediately scaling ImpactMatters analysis to millions of donors, helping them find high-impact nonprofits that advance their personal charitable mission. We could not be more excited to be a part of Charity Navigator. Elijah, Tamsin and Masha have joined the team to continue leading this work, and Dean and Michael W. are advising Charity Navigator on its ratings. We have big plans. Much of the next year will focus on helping and incentivizing nonprofits to share more public data on their impact (on that note, if you know a nonprofit, send them our way).

ImpactMatters secret to success has always been a haunting work hard culture that had us hallowing out the competition.
Jonathan, Michael I., Elijah, Tamsin, Masha, Libby (Elizabeth)
Weinstein holds forth.
Serious Business
Impact ratings = serious business
Elijah and Tamsin
Credit Jeenah Moon for The New York Times

You can learn more about the acquisition on, see an example of a rating or sign up for Charity Navigator's email list to stay up-to-date.

Our hope, and strong expectation, is that this leads to more money for the best programs and helps nonprofits better achieve their goals, in turn leading to outcomes we all want to see: longer, healthier, happier lives for people in the U.S. and around the world.

There are many people who got us here. Thank you to Tamsin Chen, our first hire. No question, we would not be here without her. She has brought consistent passion and excellence to the job and has truly been our third co-founder. A major thank you to our board - Kevin Starr, Paul Brest and Tamara Fox have dedicated their knowledge and talent over the years to making this a success. They have stuck through our setbacks and pivots. We look forward to continuing our shared work on our original product, impact audits, through Impact Audit Partners (more below). Thank you to our phenomenal staff* over the years, especially the brilliant Masha Winchell, who has come over to the Charity Navigator team, and Josh Twersky for patient, invaluable hard work, guidance and support. Thank you to the many nonprofits** who have taken their time to teach us about their work, share data and generally have a great deal of patience with us. Thank you to our funders,*** especially Chuck Slaughter at Goldsmith Foundation (which has funded us every year since inception), Hewlett Foundation (which gave us our first grant) and Bill & Melinda Gates Foundation (which funded our expansion last year, research on effective giving and this acquisition). Thank you to Shannon Coyne, who has lent constant support from Kellogg. Thank you to Annie Duflo and the Innovations for Poverty Action team for giving us a home in our first few years. Most importantly, thank you to our families (especially Cindy, Max, Maya, Gabi, Kathleen, Jim, Jasper and Elise) and friends for supporting us throughout this journey.

And thank you to you, for supporting our work in ways big and small.

Finally, thank you to the Charity Navigator team, especially Michael Thatcher, Stephen Rockwell and Kevin Scally, for making this happen and welcoming us so warmly.

The former ImpactMatters board, which Elijah has now joined, will continue working together as a Board of a renamed entity, Impact Audit Partners. This new entity will return to the earlier iterations of ImpactMatters and our effort to establish an "impact audit" as a standard for the nonprofit sector, as well as to facilitate and promote research on approaches to inspire more effective philanthropy. We believe impact audits have the potential to reward excellence in impact evaluation and support better grantmaking, pushing the nonprofit sector forward. We will be working on a strategic plan for the new entity in the coming year. Please get in touch if you want to learn more, or want to collaborate in some way.

ImpactMatters has always been motivated by a simple idea: when we are making decisions about something so precious and scarce as charitable dollars, we should do so with the best possible information so that we can support the work that is going to help the most people, the most. Although ImpactMatters is going away, we are thrilled to be starting the next chapter of this work at Charity Navigator. We would love to hear your thoughts, especially about what is next. You can always reach us at and

Dean and Elijah

Dean testifies, Elijah live tweets

More much deserved thank yous

To our staff over the years

  • Neil Mirochnik, who was tasked with developing the very first iteration of the idea that would become our ratings years later.
  • Benjamin Mazzotta, our first research director who was instrumental in many of the early impact audits.
  • Josh Twerksy who made Elijah's life so much better by taking excellent command of our finance, HR and other functions (and doing impact analysis!)
  • Alanna Jagielski who tackled the difficult task of setting up marketing and fundraising operations.
  • Verónica Vázquez Ugalde, who, in addition to excellent analysis and patient nonprofit troubleshooting, was perpetually cheery.
  • Catherine Darin, an exceptional analyst and wonderful presence in the office.
  • Luisa Rodriguez, who always pushed us to do better analysis and focus on the ultimate goal of helping more people.
  • Stephen Nuñez, a methodology genius who built many of the algorithms and supporting systems we still use (and taught us many, many random facts).
  • Elizabeth Denault, who expertly led the rollout of our new rating system.
  • Dmitry Popov, a brilliant (and available!) engineer who patiently turned our vision for guided impact reporting into a reality.
  • Catalin Coroeanu (also available!) for expertly building our ratings site.
  • Our other freelancers over the years.
Coincidental Twinning: A Retrospective
Left to right, top to bottom: Tamsin, Veronica, Michael, Jonathan, Elijah, Neil, Tamsin, Luisa, Masha, Tamsin, Katie Choi, Tamsin, Michael, Tamsin, Masha, Tamsin again. Unrelated: Molly, Renatta, Leo, Millie, Jonathan drawing
Times Square Roof
Tamsin, Masha and Josh at our Times Square office
Rigorous analysis
Catherine, Josh and Tamsin capturing the thrill of rigorous data analysis (credit: Luisa, props and lighting: Elijah, morale: Veronica)
Coin photoshoot
From our in-house photoshoot. It took a couple of hours, but eventually we successfully went with a stock photo.

Thank you to the nonprofits we worked with along the way

Thank you to the nonprofits we worked with along the way. Special thanks to BOMA Project, Success for All Foundation, Trickle Up and Possible, who were game for participating in the first version of the impact audit, and to Samasource, our first paying client. Thanks also to Africare, CHEF, City Education Partners, Development Media International, D-Rev, Evidence Action, Fedcap, Feeding America, Genesys Works, G.N.Y.C., Integrate Health, International Samaritan, Kilgoris Project, Living Goods, Muso, Opportunity Junction, Per Scholas, Prosecutor Impact, Sightsavers, TechnoServe, Village Enterprise, Win and all who participated in guided impact reporting.

Thank you to our funders

Bezos Family Foundation, Bill & Melinda Gates Foundation, BlackRock Foundation, Carson Family Charitable Trust, Dean Karlan, Delta Fund, Fran Schwartz, Goldsbury Foundation, Henry Jarecki, Hewlett Foundation, Horace W. Goldsmith Foundation, Ira and Katya Handler, John Corey, Leonard Bell, Matt Stolzar, Michael M. Weinstein, Mulago Foundation, Nicholas Wade, Paul Brest, Paul Tudor Jones Family Foundation, and Tipping Point Foundation.

Thank you to the others who helped along the way

  • Northwestern's Kellogg School of Management
  • Jonathan Vayness from Kellogg School, who took on the major task of understanding the impact of major nonprofits.
  • Michael Ioannou from Kellogg School, whose eye for detail and can-do spirit helped get our new ratings system to the finish line.
  • Susan Athey, Leah Rosenzweig, Henrike Steimer and the whole Stanford University team for such a stimulating research collaboration.
  • Thanks also to Akruti Desai, Victoria Vrana and Parastou Youssefi from Bill & Melinda Gates Foundation; Jacob Harold, Eva Nico and the Candid/GuideStar team; Ellen Chandler and Daniela Kaisth from Falconwood Foundation; Jeff Mosenkis from Innovations for Poverty Action; Charlie Bressler, Peter Singer and The Life You Can Save team; GiveWell (for constant inspiration); Sarah Gelfand from Fidelity Charitable; Victoria Kelberer and Magda Swanson from Vanguard Charitable; Nick Fitz and Ari Kagan from Momentum; Caroline Fiennes of Giving Evidence; and Sarah Holloway from Columbia.
  • Our interns over the years, who delivered excellent work despite the fact we were still figuring out what they should be doing most of the time.
    • Summer 2016: Katie (Yoonyoung) Choi, Kenny Hofmeister and Marcela Macias
    • Fall 2016: Shreya Chandra, Chuba Ezekwesili, Tong Li, Yilin Tian, Wenyue Yang and Danyun Zhou
    • Summer 2017: Emma Lower, Josh Totte, Veronica Vazquez Ugalde and Grace Vogelzang
    • Fall 2017: David Maravilla, Vyana McIntyre, Tarang Singhal and Giovanni Zenteno
    • Summer 2018: Kiren McKean
    • Fall 2018: Danae Flores
    • Summer 2019: Ronela Haxhiaj, Thuy Le and Edgar Wibisono
Summer 2017 crew in Boston: Ben, Tamsin, Josh Totte, Veronica, Emma Lower and Grace Vogelzang
  • Sabine Horner and Kallie Knop for expertly guiding our ratings press launch and wracking up an impressive number of articles.
  • Consultants Nate Falkner and Matt Joyce for hustling hard to sell the impact audit.
  • Matt Schwartz and the whole Constructive team for our beautiful website.
  • Angela Campbell and Agora for Good for giving us a platform for reaching individual donors.
  • Thanks to the many nonprofit and foundation professionals who helped us; they are too many to list, but we especially want to thank Jamie Austin, Celeste Brubaker, Dianne Calvi, Molly Christiansen, Erin Crossett, Alissa Friedman, Grace Hollister, Ieva Kajokaite, the late Leila Janah, Tony MacDonald, Twisha Mehta, Grace Morgan, Kate Scaife Diaz, Sara Tollefson, Caitlin Tulloch and Cathryn Wood.
  • Dean thanks Lilly Chang, Shannon Coyne, Sana Khan, Wendy Lewis, Ann Motogawa, Grace Musante, Isabel Oñate, and Sneha Stephen, who all, in various capacities and times over the past five years, have helped him stay sane and productive in helping ImpactMatters develop.
  • Elijah thanks Travis Powell for a sympathetic ear over now 13 years and three professional phases and the Walimu team for inspiration, motivation and patience.