Laa ilaaha illallaah, wahdahu laa syariika lah, lahul mulku wa lahul hamd, wa huwa 'alaa kulli syai-in qodiir.
(None has the right to be worshipped except Allah, alone, without partner, to Him belongs all sovereignty and praise, and He is over all things omnipotent.)
English: Hisn al-Muslim (hisnmuslim.com), item 93
Guidance: Recited on the Day of Arafah. The source introduces it with a hadith about the best dua; see its page
(13)HR. At-Tirmidzi dan lihat Shahih At-Tirmidzi 3/ 184. Al-Albani menyatakan, hadits tersebut adalah hasan. Lihat pula Al-Ahaditsush Shahihah lil-Albani 4/6.