Being a large thirteen member boy band, the members contain a variety of different vocal ranges to complement each other when singing, espcially in their fast dance tracks and slow ballads that requires harmonization. Yesung, Kang-In, Siwon and Kyuhyun sing within a deep bass range. However, they are also known for their vocal belting techniques, notably Yesung and Kyuhyun.^[51] On the other hand, Sungmin and Ryeowook sing within a high tenor range while Leeteuk, Heechul, Han Geng, and Donghae's vocals come between as a mid-high range. Most non-lyrical introductions or bridges are usually harmonized by Super Junior K.R.Y. They can also be seen singing short acappella cuts^[e], and are considered by many to be the most talented vocalists in the group.^[52] Shindong, Eunhyuk and Kibum are the known rappers of the group due to their rhythmical vocal range and quick tongue. Heechul and Donghae conistently rap as the supporting vocals.^[f]

Super Junior has been criticized in the past for lip-synching and lack of vocal skills, specifically for shaky pitch and heavy breathing.^[53][54] The criticisms worsened in July 2006 when they lipsynched on Show! Music Core (쇼! 음악중심) of MBC, a show that guarantees all live performances. Though fans have defended them, saying that Heechul was ill, their critics do not accept this explanation. They argue that since the band contains 13 members, one ill singer should not necessitate lipsynching by the entire group.^[55] Despite this, they have still remained popular through their strong fan base and their album sales have been strong.