  For a finite group $G$, we denote by $c(G)$, the minimal degree of faithful
representation of $G$ by quasi-permutation matrices over the complex field
$\mathbb{C}$. For an irreducible character $\chi$ of $G$, the codegree of
$\chi$ is defined as $\cod(\chi) = |G/ \ker(\chi)|/ \chi(1)$. In this article,
we establish equality between $c(G)$ and a $\mathbb{Q}_{\geq 0}$-sum of
codegrees of some irreducible characters of a non-abelian $p$-group $G$ of odd
order. We also study the relation between $c(G)$ and irreducible character
codegrees for various classes of non-abelian $p$-groups, such as, $p$-groups
with cyclic center, maximal class $p$-groups, GVZ $p$-groups, and others.
