The Prophet (ﷺ) used to say when he breaks his fast:
ذَهَبَ الظَّمَاءُ وَابْتَلَّتِ الْعُرُوْقُ وَثَبَتَ الْأَجْرُ إِنْ شَاءَ اللَّهُ
Pronunciation
Dhahabadh-dhama'u wabtallatil-'urooqu, wa thabatal-'ajru 'inshaa'Allah
Meaning
The thirst is gone, the veins are moistened and the reward is confirmed, if Allah wills. Note that, the widely practiced hadith 'Allahumma laka samtu wa 'ala rizqika aftartu' but, the hadith is da'if (weak). [2]
Source: [1] Hasan (Albani). Abu Dawud: 2357 [2] Weak (Albany). Abu Dawud: 2358
Read the hadith
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مُحَمَّدِ بْنِ يَحْيَى أَبُو مُحَمَّدٍ، حَدَّثَنَا عَلِيُّ بْنُ الْحَسَنِ، أَخْبَرَنِي الْحُسَيْنُ بْنُ وَاقِدٍ، حَدَّثَنَا مَرْوَانُ، - يَعْنِي ابْنَ سَالِمٍ - الْمُقَفَّعُ - قَالَ رَأَيْتُ ابْنَ عُمَرَ يَقْبِضُ عَلَى لِحْيَتِهِ فَيَقْطَعُ مَا زَادَ عَلَى الْكَفِّ وَقَالَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم إِذَا أَفْطَرَ قَالَ " ذَهَبَ الظَّمَأُ وَابْتَلَّتِ الْعُرُوقُ وَثَبَتَ الأَجْرُ إِنْ شَاءَ اللَّهُ " .
Marwan ibn Salim al-Muqaffa' said: I saw Ibn Umar holding his beard with his hand and cutting what exceeded the handful of it. He (Ibn Umar) said that the Prophet (ﷺ) said when he broke his fast: Thirst has gone, the arteries are moist, and the reward is sure, if Allah wills. [[1] Hasan (Albani). Abu Dawud: 2357 [2] Weak (Albany). Abu Dawud: 2358]
Duas from IslamicAPI's Masnun Dua dataset (based on the Quran, hadith, Hisnul Muslim and Rahe Belayat). See the dataset