The Prophet (ﷺ) said: The best supplication is the supplication on the day of 'Arafah. The best dua that the Prophet (ﷺ) recited is -
لَا إِلَهَ إِلَّا اللَّهُ وَحْدَهُ لَا شَرِيكَ لَهُ، لَهُ الْمُلْكُ وَلَهُ الْحَمْدُ وَهُوَ عَلَى كُلِّ شَيءٍ قَدِيرٌ
Pronunciation
Laa ilaaha ill-Allahu, wahdahu laa shareeka lahu, lahul-mulku wa lahul-hamdu, wa huwa ‛alaa kulli shay’in qadeer
Meaning
None has the right to be worshiped except Allah, alone, without partner. To Him belongs sovereignty and all praise and He is over all things omnipotent.
Source: Hasan (Albani). Tirmidhi: 3585
Read the hadith
حَدَّثَنَا أَبُو عَمْرٍو، مُسْلِمُ بْنُ عَمْرٍو الْحَذَّاءُ الْمَدِينِيُّ حَدَّثَنِي عَبْدُ اللَّهِ بْنُ نَافِعٍ، عَنْ حَمَّادِ بْنِ أَبِي حُمَيْدٍ، عَنْ عَمْرِو بْنِ شُعَيْبٍ، عَنْ أَبِيهِ، عَنْ جَدِّهِ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ " خَيْرُ الدُّعَاءِ دُعَاءُ يَوْمِ عَرَفَةَ وَخَيْرُ مَا قُلْتُ أَنَا وَالنَّبِيُّونَ مِنْ قَبْلِي لاَ إِلَهَ إِلاَّ اللَّهُ وَحْدَهُ لاَ شَرِيكَ لَهُ لَهُ الْمُلْكُ وَلَهُ الْحَمْدُ وَهُوَ عَلَى كُلِّ شَيْءٍ قَدِيرٌ " . قَالَ هَذَا حَدِيثٌ حَسَنٌ غَرِيبٌ مِنْ هَذَا الْوَجْهِ . وَحَمَّادُ بْنُ أَبِي حُمَيْدٍ هُوَ مُحَمَّدُ بْنُ أَبِي حُمَيْدٍ وَهُوَ أَبُو إِبْرَاهِيمَ الأَنْصَارِيُّ الْمَدَنِيُّ وَلَيْسَ هُوَ بِالْقَوِيِّ عِنْدَ أَهْلِ الْحَدِيثِ . `
Amr bin Shu`aib narrated from his father, from his grandfather, that the Prophet (ﷺ) said: “The best of supplication is the supplication of the Day of `Arafah. And the best of what I and the Prophets before me have said is: None has the right to be worshipped but Allah, Alone, without partner, to Him belongs all that exists, and to Him belongs the Praise, and He is powerful over all things. (Lā ilāha illallāh, waḥdahu lā sharīka lahu, lahul-mulku wa lahul-ḥamdu, wa huwa `alā kulli shai’in qadīr).’” [Hasan (Albani). Tirmidhi: 3585]
Duas from IslamicAPI's Masnun Dua dataset (based on the Quran, hadith, Hisnul Muslim and Rahe Belayat). See the dataset