These are the wordings said morning and evening, and the ones the Prophet ﷺ said over children. They ask Allah for shelter — from harm you can see and harm you cannot.
Nothing harms with this name said over it
بِسْمِ اللّٰهِ الَّذِي لَا يَضُرُّ مَعَ اسْمِهِ شَيْءٌ فِي الْأَرْضِ وَلَا فِي السَّمَاءِ وَهُوَ السَّمِيعُ الْعَلِيمُ
Bismillāhil-ladhī lā yaḍurru maʿa-smihi shay'un fil-arḍi wa lā fis-samā', wa Huwas-Samīʿul-ʿAlīm
In the name of Allah, with whose name nothing on earth or in the sky can cause harm; and He is the All-Hearing, the All-Knowing.
Three times in the morning and three in the evening. · 3×, morning and evening · Sunan Abī Dāwūd 5088; Sunan at-Tirmidhī 3388
When you stop somewhere unfamiliar
أَعُوذُ بِكَلِمَاتِ اللّٰهِ التَّامَّاتِ مِنْ شَرِّ مَا خَلَقَ
Aʿūdhu bi-kalimāti-llāhit-tāmmāti min sharri mā khalaq
I take shelter in the perfect words of Allah from the harm of what He has made.
When you stop at a place on a journey, or feel uneasy somewhere. · Ṣaḥīḥ Muslim 2708
Said over children
أُعِيذُكُمَا بِكَلِمَاتِ اللّٰهِ التَّامَّةِ مِنْ كُلِّ شَيْطَانٍ وَهَامَّةٍ، وَمِنْ كُلِّ عَيْنٍ لَامَّةٍ
Uʿīdhukumā bi-kalimāti-llāhit-tāmmah, min kulli shayṭānin wa hāmmah, wa min kulli ʿaynin lāmmah
I place you both in the shelter of the perfect words of Allah, from every devil and every crawling thing, and from every eye that means harm.
Over your children — the Prophet ﷺ said it over al-Ḥasan and al-Ḥusayn. · Ṣaḥīḥ al-Bukhārī 3371
Being content with Him, morning and evening
رَضِيتُ بِاللّٰهِ رَبًّا، وَبِالْإِسْلَامِ دِينًا، وَبِمُحَمَّدٍ ﷺ نَبِيًّا
Raḍītu billāhi Rabban, wa bil-islāmi dīnan, wa bi-Muḥammadin ﷺ nabiyyā
I am content with Allah as my Lord, with Islam as my way, and with Muhammad ﷺ as my Prophet.
Three times in the morning and three in the evening. · 3×, morning and evening · Sunan Abī Dāwūd 5072
Two are tied to a time: morning and evening, and one is said three times. The wording said over children can be said over anyone you are worried for.
Every du'ā above can be heard aloud. Where the words are Qur'an, the Arabic comes from the Quran.com API and is shown exactly as served, with a link into the muṣḥaf.