You can have Forstner bits in almost any size but not smaller than 1/4 inch. However, they do go up to very big sizes with diameters of many inches. Several suppliers provide Forstner bits in diameters up to 4′′. Beyond 2′′, sizes usually rise in 1/8" steps. The larger sizes, which are particularly cost-effective, are the true benefit of this type of drill bit.