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
قُلْ 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.)
Hasanاللَّهُمَّ إِنِّي أَعُوذُ بِكَ مِنَ الْكُفْرِ وَالْفَقْرِ وَعَذَابِ الْقَبْرِ
O Allah, I seek refuge in You from disbelief, poverty, and the punishment of the grave.
Sahihأَسْتَغْفِرُ اللَّهَ أَسْتَغْفِرُ اللَّهَ أَسْتَغْفِرُ اللَّهَ اللَّهُمَّ أَنْتَ السَّلَامُ وَمِنْكَ السَّلَامُ تَبَارَكْتَ يَا ذَا الْجَلَالِ وَالْإِكْرَامِ
I seek Allah's forgiveness (three times). O Allah, You are Peace and from You is peace. Blessed are You, O Owner of Majesty and Honor.
Sahihرَبَّنَا لَا تُزِغْ قُلُوبَنَا بَعْدَ إِذْ هَدَيْتَنَا وَهَبْ لَنَا مِن لَّدُنكَ رَحْمَةً ۚ إِنَّكَ أَنتَ الْوَهَّابُ
Our Lord, do not let our hearts deviate after You have guided us, and grant us mercy from Yourself. Indeed, You are the Bestower.
Sahih