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Homeomorphism classes are:

• no holes corresponding with C, G, I, J, L, M, N, S, U, V, W, and Z;
• no holes and three tails corresponding with E, F, T, and Y;
• no holes and four tails corresponding with X;
• one hole and no tail corresponding with D and O;
• one hole and one tail corresponding with P and Q;
• one hole and two tails corresponding with A and R;
• two holes and no tail corresponding with B; and
• a bar with four tails corresponding with H and K; the "bar" on the K is almost too short to see.

Homotopy classes are larger, because the tails can be squished down to a point. They are:

• one hole,
• two holes, and
• no holes.

To classify the letters correctly, we must show that two letters in the same class are equivalent and two letters in different classes are not equivalent. In the case of homeomorphism, this can be done by selecting points and showing their removal disconnects the letters differently. For example, X and Y are not homeomorphic because removing the center point of the X leaves four pieces; whatever point in Y corresponds to this point, its removal can leave at most three pieces. The case of homotopy equivalence is harder and requires a more elaborate argument showing an algebraic invariant, such as the fundamental group, is different on the supposedly differing classes.

Letter topology has practical relevance in stencil typography. For instance, Braggadocio font stencils are made of one connected piece of material.