Randall is derived from a medieval name composed of two elements: "shield" or "rim" + "wolf". ... There are several variant spellings of the English given name; these include Randal, Randel, Randell, and Randle. The pet form is Randy.
Randi is both a given name, and a nickname in the English language, popular in North America and Norway. It is primarily a feminine name, although there is recorded usage of the name by men. It may have originated as a pet form of Miranda or as a feminine form of Randy.