Sirius is a binary star system, with the primary star, Sirius A, being a white main-sequence star. It is significantly larger than Algol.

Algol is a triple star system, with the primary star, Algol A, being a blue-white subgiant star. While Algol A is larger than our Sun, it is still significantly smaller than Sirius A.

Comparison of Sizes:

* Sirius A: 1.71 times the radius of the Sun

* Algol A: 3.6 times the radius of the Sun

Therefore, Sirius is larger than Algol.