How many rounds does a glock?

The Glock 17 (full-size 9mm) holds 17 rounds in a factory magazine.

The Glock 19 (compact 9mm) holds 15 rounds in a factory magazine.

The Glock 26 (teeny-tiny 9mm) holds 10 rounds in a factory magazine.

The Glock 17L/34 (competition) also holds 17 rounds.