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Real Change For Your Dollar
GiveWell is a charity evaluator created in 2007 by two former investment analysts, Holden Karnofsky and Elie Hassenfeld.

Many Effective Altruists donate to GiveWell's top recommendations, because they evaluate charities based on impact, rather than metrics that are mostly irrelevant such as 'Overhead Ratio'.

GiveWell Philosophy

GiveWell evaluates charities according to how much good they achieve per dollar.

GiveWell says:

"Unlike charity evaluators that focus solely on financials, assessing administrative or fundraising costs, we conduct in-depth research aiming to determine how much good a given program accomplishes (in terms of lives saved, lives improved, etc.) per dollar spent."[1]