Upon completing the ablution › Wudu & Purification
Dua after ablution — repentance and purity
اللّهُـمَّ اجْعَلنـي مِنَ التَّـوّابينَ وَاجْعَـلْني مِنَ المتَطَهّـرين.
Allahummaj-AAalnee minat-tawwabeena wajAAalnee minal-mutatahhireen.
Translation
O Allah, make me of those who return to You often in repentance and make me of those who remain clean and pure.