Weight-based dosing is vulnerable to error due to inaccurate estimation of body weight, use of metric vs. non-metric units, or patients being underweight or overweight. This commentary suggests strategies for reducing weight- and size-based dosing errors including reduction in reliance on estimated body weight, standardizing descriptor (e.g., body mass index), limiting options in the electronic health record (EHR), and integrating complex calculations into the EHR.