We propose that some products carry labels that mimic the features of certified health and sustainability labels and that such lookalike labels can confuse consumers into believing that a product has specific, desirable attributes. To address this, we develop a mouse-tracking method for measuring consumer confusion about product attributes. In Study 1, we show that lookalike labels often mislead consumers into believing a product includes a certified label, and that mouse cursor movements provide insights into confusion levels. By applying signal-detection theory to mouse cursor movements, we develop a novel metric that quantifies product attribute confusion and accurately flags products as either “attribute confusion suspect” or “attribute confusion safe”. In Study 2, we replicate our findings and show that attribute confusion is associated with a higher willingness-to-pay. In Study 3, we test the robustness of the metric under different exposure times. The novel attribute confusion metric provides marketers, policymakers, and consumer advocacy groups with a tool to design less confusing labels and can serve as evidence in cases where a product is suspected of misleading consumers or copycatting certified or trademarked labels.