A glass composition including SiO2 in an amount from 60.0 to 73.01% by weight, Al2O3 in an amount from about 13.0 to about 26.0% by weight, MgO in an amount from about 5.0 to about 12.75% by weight, CaO in an amount from about 3.25 to about 4.0% by weight, Li2O in an amount from about 3.25 to about 4.0% by weight, and Na2O in an amount from 0.0 to about 0.75% by weight is provided. Glass fibers formed from the inventive composition may be used in applications that require high strength, high stiffness, and low weight. Such applications include, but are not limited to, woven fabrics for use in forming wind blades, armor plating, and aerospace structures.