We exploit a unique dataset from a price comparison site to estimate the determinants of clicks received by online retailers. We find that a firm enjoys a 60% jump in its clicks when it offers the lowest price at the site, and failure to account for discontinuities distorts parameter estimates by nearly 100%. This discontinuity is consistent with a variety of models that have been used to rationalize online price dispersion. Finally, we show that one may use estimates of the determinants of a firm’s clicks to obtain bounds on its underlying demand parameters, including standard elasticities of demand.