Allahumma anta rabbi la ilaha illa anta khalaqtanee wa ana abduka wa ana a'la a'hdika wa w'adika mastat'atu auzhubika min sharri ma sana'atu abuo laka bini'amatika alayya wa abou bizhambi fagfirli fainnahu la yagfiruzhunuba illa anta.
Oh Allah, you are my lord. None has the right to be worshiped except you. You created me and I am Your servant and I abide to Your covenant and promise (to honor it) as best I can. I take refuge in You from the evil of which I committed. I acknowledge Your favor upon me and I acknowledge my sin. So forgive me for verily none can forgive sins except You.
Prophet Muhammed (PBUH) has been recorded as saying, " If somebody recites it during the day with firm faith in it and dies on the same day before the evening, he will be from the people of Paradise and if somebody recites it at night with firm faith in it and dies before the morning he will be from the people of Paradise"(mentioned in Sahih Al Bukhari).
I just want to clarify the meaning of this statement else people will think they will land in Paradise by just reading this dua. You need to ask daily, with sincere devotion to Allah to forgive your sins. Once you are void of sins, you enter Paradise and this is what our Prophet meant to say through his statement. So, ask for forgiveness, do good deeds...in essence, be a good Muslim so you can enter Paradise.
103.5 - Ahmad