Are contact lens prescriptions stronger than glasses?

No, this is a misunderstanding of how contacts and glasses work. The ‘strength’ of the prescription is dependent on the eye’s ability to focus an image on the retina. Contact lenses sit on the eye, closer by about 12mm to the retina than a pair of glasses. So they have to bend the light less to achieve the same result. While they are different, they end up focusing the image on the same spot. So while the result to correction eye vision is the same, the parameters between contacts and glasses are different, and not translatable.