The phrase "am on par" indicates that someone or something is equal in status or ability to another. Antonyms for this phrase would refer to situations or people that are not equal or equivalent. Words like inferior, lower, beneath, and underdog could be antonyms for "am on par." These words would imply a person or group is below or less capable than others. Conversely, words like superior, overachiever, elite, and top-performer would indicate a person or group that is above or excels beyond others. Therefore, when looking for antonyms for "am on par", it is necessary to consider words that describe both lower and higher status or ability.