Niyyah is the intention in the heart before an act of worship in Islam.
The Arabic term niyyah refers to the inner purpose or resolve behind an action, especially when a person performs it for the sake of God. It helps distinguish an act of worship from an ordinary action that may look similar outwardly.
Niyyah is especially important in practices such as salah, fasting and Hajj. For Ramadan fasting, the intention concerns undertaking the fast as an act of obedience, rather than simply going without food or drink for health, habit or another reason.
A frequent misunderstanding is that niyyah must be spoken aloud in a fixed formula. Many Islamic scholars emphasize that it is fundamentally an act of the heart, and note that there is no established requirement for a person to audibly recite an intention before prayer. The concept is closely connected with the famous Islamic principle that deeds are judged by intentions.