اللَّهُمَّ ارْحَمْنِي بِالْقُرْآنِ وَاجْعَلْهُ لِي إِمَامًا وَنُورًا وَهُدًى وَرَحْمَةً
Allahummar-hamni bil-Quran waj'alhu li imaman wa nuran wa hudan wa rahmah
O Allah, have mercy on me through the Quran, and make it for me a guide, a light, a source of guidance, and a mercy.
It is Sunnah to make du'a after completing a reading of the entire Quran (khatm). Ramadan is when many Muslims complete one or more readings. This is one of the recommended du'as — asking Allah to make the Quran transform your life, not just words you recited.
Related Du'as
اللَّهُمَّ أَعِنِّي عَلَى صِيَامِهِ وَقِيَامِهِ
O Allah, help me to fast and pray during it (Ramadan).
Atharتَقَبَّلَ اللَّهُ مِنَّا وَمِنْكُمْ
May Allah accept from us and from you.
Hasanذَهَبَ الظَّمَأُ وَابْتَلَّتِ الْعُرُوقُ وَثَبَتَ الْأَجْرُ إِنْ شَاءَ اللَّهُ
The thirst is gone, the veins are moistened, and the reward is confirmed, if Allah wills.
Hasanاللَّهُمَّ لَكَ صُمْتُ وَعَلَى رِزْقِكَ أَفْطَرْتُ
O Allah, for You I have fasted and with Your provision I break my fast.
Hasan