Ibn 'Abbas (RA) said: when The Prophet (ﷺ) was standing at night to pray Tahajjud, he used to recite:

اَللَّهُمَّ لَكَ الْحَمْدُ أَنْتَ قَيِّمُ السَّمَوَاتِ وَالْأَرْضِ وَمَنْ فِيهِنَّ وَلَكَ الْحَمْدُ، لَكَ مُلْكُ السَّمَوَاتِ وَالْأَرْضِ وَمَنْ فِيهِنَّ، وَلَكَ الْحَمْدُ أَنْتَ نُورُ السَّمَوَاتِ وَالْأَرْضِ، وَلَكَ الْحَمْدُ أَنْتَ الْحَقُّ، وَوَعْدُكَ الْحَقُّ، وَلِقَاؤُكَ حَقٌّ، وَقَوْلُكَ حَقٌّ، وَالْجَنَّةُ حَقٌّ، وَالنَّارُ حَقٌّ، وَالنَّبِيُّونَ حَقٌّ، وَمُحَمَّدٌ ﷺ حَقٌّ، وَالسَّاعَةُ حَقٌّ، اَللَّهُمَّ لَكَ أَسْلَمْتُ، وَبِكَ آمَنْتُ وَعَلَيْكَ تَوَكَّلْتُ، وَإِلَيْكَ أَنَبْتُ، وَبِكَ خَاصَمْتُ، وَإِلَيْكَ حَاكَمْتُ، فَاغْفِرْ لِي مَا قَدَّمْتُ وَمَا أَخَّرْتُ، وَمَا أَسْرَرْتُ وَمَا أَعْلَنْتُ، أَنْتَ الْمُقَدِّمُ وَأَنْتَ الْمُؤَخِّرُ، لَا إِلَهَ إِلَّا أَنْتَ (لَا إِلَهَ غَيْرُكَ)

Allaahumma lakal-hamdu. Anta qaiyyimus-samawaati wal-ardi wa man fihinna. Walakal-hamdu, Laka mulkus-samawaati wal-ardi wa man fihinna. Walakal-hamdu, anta nurus-samawaati wal-ardi. Walakal-hamdu, antal-haqqu wa wa'dukal-haqqu, wa liqaa'uka Haqqun, wa qauluka Haqqun, wal-jannatu Haqqun wan-naaru Haqqun wannabiyuna Haqqun. Wa Muhammadun (ﷺ) Haqqun, was-sa'atu Haqqun. Allaahumma Laka aslamtu wabika amantu, wa 'Alaika tawakkaltu, wa ilaika anabtu wa bika khaasamtu, wa ilaika ‘haakamtu faghfir li maa qaddamtu wamaa akh-khartu wamaa as-rartu wamaa a’lantu, antal-muqaddimu wa antal muakh-khiru, laa ilaaha illaa anta (in another narration there is laa ilaaha ghairuka instead of laa ilaaha illaa anta)

O Allah! All the praises are for you, You are the Holder of the Heavens and the Earth, And whatever is in them. All the praises are for You; You have the possession of the Heavens and the Earth And whatever is in them. All the praises are for You; You are the Light of the Heavens and the Earth And all the praises are for You; You are the King of the Heavens and the Earth; And all the praises are for You; You are the Truth and Your Promise is the truth, And to meet You is true, Your Word is the truth And Paradise is true And Hell is true And all the Prophets (Peace be upon them) are true; And Muhammad (ﷺ) is true, And the Day of Resurrection is true. O Allah ! I surrender (my will) to You; I believe in You and depend on You. And repent to You, And with Your help I argue (with my opponents, the non-believers) And I take You as a judge (to judge between us). Please forgive me my previous And future sins; And whatever I concealed or revealed And You are the One who make (some people) forward And (some) backward. There is none to be worshipped but you.

Reference: Bukhari: 1120