أَسْتَغْفِرُ اللَّهَ أَسْتَغْفِرُ اللَّهَ أَسْتَغْفِرُ اللَّهَ
Astaghfirullah, Astaghfirullah, Astaghfirullah
I seek Allah's forgiveness (three times).
The very first thing the Prophet ﷺ would say after giving the salam in prayer — before any other dhikr. Three times. You just finished standing before Allah, bowing, prostrating — yet the first thing you say is "forgive me." Why? Because no prayer is perfect. Your mind wandered, your khushu' wavered, your standing was imperfect. Istighfar after prayer is humility about the quality of your worship.
Related Du'as
لَا إِلَٰهَ إِلَّا اللَّهُ وَحْدَهُ لَا شَرِيكَ لَهُ لَهُ الْمُلْكُ وَلَهُ الْحَمْدُ وَهُوَ عَلَى كُلِّ شَيْءٍ قَدِيرٌ، اللَّهُمَّ لَا مَانِعَ لِمَا أَعْطَيْتَ وَلَا مُعْطِيَ لِمَا مَنَعْتَ وَلَا يَنْفَعُ ذَا الْجَدِّ مِنْكَ الْجَدُّ
There is no deity except Allah, alone without partner. His is the dominion and His is the praise, and He is over all things capable. O Allah, none can withhold what You have given, and none can give what You have withheld, and no wealth or might can benefit anyone against You.
Sahihاللَّهُ لَا إِلَٰهَ إِلَّا هُوَ الْحَيُّ الْقَيُّومُ ۚ لَا تَأْخُذُهُ سِنَةٌ وَلَا نَوْمٌ ۚ لَهُ مَا فِي السَّمَاوَاتِ وَمَا فِي الْأَرْضِ ۗ مَن ذَا الَّذِي يَشْفَعُ عِندَهُ إِلَّا بِإِذْنِهِ ۚ يَعْلَمُ مَا بَيْنَ أَيْدِيهِمْ وَمَا خَلْفَهُمْ ۖ وَلَا يُحِيطُونَ بِشَيْءٍ مِّنْ عِلْمِهِ إِلَّا بِمَا شَاءَ ۚ وَسِعَ كُرْسِيُّهُ السَّمَاوَاتِ وَالْأَرْضَ ۖ وَلَا يَئُودُهُ حِفْظُهُمَا ۚ وَهُوَ الْعَلِيُّ الْعَظِيمُ
Allah! There is no deity except Him, the Ever-Living, the Sustainer of existence. Neither drowsiness overtakes Him nor sleep. To Him belongs whatever is in the heavens and whatever is on the earth. Who can intercede with Him except by His permission? He knows what is before them and what will be after them, and they encompass not a thing of His knowledge except for what He wills. His Kursi extends over the heavens and the earth, and their preservation tires Him not. And He is the Most High, the Most Great.
Sahihاللَّهُمَّ لَا تَدَعْ لَنَا ذَنْبًا إِلَّا غَفَرْتَهُ وَلَا هَمًّا إِلَّا فَرَّجْتَهُ وَلَا دَيْنًا إِلَّا قَضَيْتَهُ وَلَا حَاجَةً مِنْ حَوَائِجِ الدُّنْيَا وَالْآخِرَةِ إِلَّا قَضَيْتَهَا بِرَحْمَتِكَ يَا أَرْحَمَ الرَّاحِمِينَ
O Allah, leave no sin of ours except that You forgive it, no worry except that You relieve it, no debt except that You settle it, and no need of this world or the next except that You fulfill it, by Your mercy, O Most Merciful of the merciful.
Hasanقُلْ هُوَ اللَّهُ أَحَدٌ اللَّهُ الصَّمَدُ لَمْ يَلِدْ وَلَمْ يُولَدْ وَلَمْ يَكُن لَّهُ كُفُوًا أَحَدٌ قُلْ أَعُوذُ بِرَبِّ الْفَلَقِ قُلْ أَعُوذُ بِرَبِّ النَّاسِ
Say: He is Allah, the One. Allah, the Eternal Refuge. He neither begets nor is born. Nor is there any equivalent to Him. Say: I seek refuge in the Lord of daybreak. Say: I seek refuge in the Lord of mankind. (Recite each surah in full — once after every prayer, three times after Fajr and Maghrib.)
Hasan