For the pre-dawn meal known as Suhoor, especially during the month of Ramadan, the following dua is commonly recited to affirm the intention to fast:
وَبِصَوْمِ غَدٍ نَّوَيْتُ مِنْ شَهْرِ رَمَضَانَ
Wa bisawmi ghadinn nawaiytu min shahri Ramadan
Translation:
“I intend to keep the fast for tomorrow in the month of Ramadan.”
This dua is said after finishing the Suhoor meal, at the time of the Fajr prayer, to express the intention to fast for the upcoming day[1][3][5].