How do you tell if cuticle oil is bad?

You can tell if cuticle oil is bad by checking for changes in its appearance, such as separation, cloudiness, or discoloration. Additionally, if the oil has an off or rancid smell, it may have gone bad. Expired or improperly stored oils may lose their effectiveness, so always check the expiration date and store them in a cool, dark place. If in doubt, it’s best to discard it and get a fresh bottle.