Lift the toilet seat and lid
Measure the distance from the center of the two seat hinge holes to the front edge of the bowl
Measure the distance between the two hinge holes
Measure the widest point of the toilet bowl
Measure the length of the toilet bowl from the front edge to the center of the hinge holes
Check whether the bowl shape is round or elongated
Compare your measurements to the replacement seat dimensions
Verify the hinge style and bolt spacing before buying a new seat