mdcalc.com
MDCalc is a source for medical equations, algorithms, scores, and guidelines. It offers a library of calculators, including the Cockcroft-Gault creatinine clearance equation, a weight-based levothyroxine dose calculator, CKD-EPI GFR equations, mean arterial pressure, and the SpO₂/FiO₂ ratio. Tools can be browsed by specialty and filtered by calculation purpose.