Cognomen Jernes (Jernes 
) , worldwide, is a very rare family name. The cognomen Jernes is habitual in Norway, where it is a rare surname, Israel, where it is a very rare surname, and Venezuela, where it is an extremely rare surname. Measured by absolute frequency, the name is most common in Norway, India, and Venezuela. Likewise, Jernes is the forename as well as the last name.