Ramadan and Fasting Dua with Sources

Dua for Keeping the Fast at Suhoor (Source: Abu Dawud) 

Transliteration: Wa bisawmi ghadinn nawaiytu min shahri Ramadan.

Dua for Breaking the Fast

Dua 1:

Transliteration: Allahumma inni laka sumtu wa bika aamantu [wa 'alayka tawakkaltu] wa ‘ala rizq-ika aftarthu

Source: Abu Dawud

Dua 2:

Meaning: The thirst has gone and the veins are quenched, and reward is confirmed, if Allaah wills.

Transliteration: Zahabadh-dhama'u wabtallatil-'urooqu, wa thabatal-ajru inshaa-Allaahu.
Source: Abu Dawud 2/306, Sahih Al-Jami As Saghir 4/209

Dua 3:

Meaning: O Allaah, I ask You by Your mercy which envelops all things, that You forgive me.

Transliteration: Allahumma innee as'aluka bi-rahmatikal-latee wasi'ath kulla shai'in an taghfira lee.

Source: Ibn Majah 1/557

Dua for Sighting the Crescent Moon

Meaning: Allaah is the greatest. O Allaah, let the crescent loom above us in safety, faith, peace, and Islaam, and in agreement with all that You love and pleases You. Our Lord and your Lord is Allaah.

Transliteration: Allahu Akbar, Allaahumma ahillahu 'alaina bil-amni wal-imaani, was-salaamati wal-Islaami, wat-tawfeeqi limaa tuhibbu wa tardhaa, Rabbunaa wa Rabbukallaahu.

Source: At Tirmidhi 5/504

Dua for Laila tul Qadr

Meaning: O Allah You are The One Who pardons greatly, and loves to pardon, so pardon me. 

Transliteration: Allahumma innaka 'affuwwun tuhibbul 'afwa fa'fu 'anni.
Source: Tirmidhi and Ibn Majah