The Kalma Tayyib or Kalma Paak is not mentioned in Quran as a complete sentence as recited, but its first phrase "La ilaha ill-Allah" there is no god but Allah occurs twice in the Quran (37:35, 47:19).
The second phrase "Muhammadur Rasulullah" Muhammad is Rasul of Allah occurs only once in Quran (48:29). The second part was added after migration to Madina.
KALMA PAAK
Re: KALMA PAAK
Amongst Ismailis, the Kalama Pak has been the same but during different era, more declaration of faith was added. In particular the periode of 40 years between 1164 and 1204 CE has seen the namaz replaced by a very long Kalma some of which can still be found in third chapter of the current Dua.