اللَّهُمَّ أَنْتَ رَبِّي لَا إِلَهَ إِلَّا أَنْتَ، خَلَقْتَنِي وَأَنَا عَبْدُكَ، وَأَنَا عَلَى عَهْدِكَ وَوَعْدِكَ مَا اسْتَطَعْتُ، أَعُوذُ بِكَ مِنْ شَرِّ مَا صَنَعْتُ، أَبُوءُ لَكَ بِنِعْمَتِكَ عَلَيَّ، وَأَبُوءُ لَكَ بِذَنْبِي، فَاغْفِرْ لِي، فَإِنَّهُ لَا يَغْفِرُ الذُّنُوبَ إِلَّا أَنْتَ
Allāhumma anta rabbī lā ilāha illā ant, khalaqtanī wa ana ʿabduk, wa ana ʿalā ʿahdika wa waʿdika mastaṭaʿt, aʿūdhu bika min sharri mā ṣanaʿt, abūʾu laka bi-niʿmatika ʿalayya, wa abūʾu laka bi-dhambī, faghfir lī, fa-innahū lā yaghfirudh-dhunūba illā ant
O Allah, You are my Lord, there is no god but You. You created me and I am Your servant, and I keep Your covenant and promise as best I can. I seek refuge in You from the evil of what I have done. I acknowledge Your favour on me and I acknowledge my sin, so forgive me, for none forgives sins but You.
Sahih al-Bukhari 6306, from Shaddad ibn Aws