Dua for entering the bathroom, and leaving it.

Seeking refuge before entering the toilet and asking forgiveness on leaving are both sunnah.

Dua 1

بِسْمِ اللَّهِ، اللَّهُمَّ إِنِّي أَعُوذُ بِكَ مِنَ الْخُبُثِ وَالْخَبَائِثِ

Bismillāh. Allāhumma innī aʿūdhu bika minal-khubuthi wal-khabāʾith

In the name of Allah. O Allah, I seek refuge in You from the male and female devils. (Before entering, left foot first.)

Sahih al-Bukhari 142; Sahih Muslim 375; Bismillah from Jami at-Tirmidhi 606

Dua 2

غُفْرَانَكَ

Ghufrānak

I seek Your forgiveness. (After leaving, right foot first.)

Sunan Abi Dawud 30; Jami at-Tirmidhi 7

Our teachers will check the Arabic and transliteration on this page before launch.

Guide

When and how to say it.

Seeking refuge before entering the toilet and asking forgiveness on leaving are both sunnah.

Say the first dua before stepping in, not inside. Enter with the left foot and leave with the right. Do not take the mushaf or anything with Allah's name in openly.

Sahih al-Bukhari 142; Sahih Muslim 375; Bismillah from Jami at-Tirmidhi 606
Sunan Abi Dawud 30; Jami at-Tirmidhi 7

Questions

Good to know.

What do you say before entering the bathroom?

Bismillah, Allahumma inni audhu bika minal-khubuthi wal-khabaith (Bukhari 142).

What do you say after leaving the bathroom?

Ghufranak, "I seek Your forgiveness" (Abu Dawud 30).