Well, the Hijri date 20 Dhul Qidah 1385 corresponds to the Gregorian date Saturday, 12 March 1966. This date lies in the eleventh month of the Hijri year 1385 AH, which is Dhu Al-Qidah of 1385 AH. Both this Hijri and Gregorian date occur on the single day that is Saturday without any doubt. The Arabic date 1385/11/20 is calculated using the Umm Al-Qura calendar and the sighting of the moon. One thing to remember is that this Arabic date may occur on different Gregorian date depending upon the region and country and obviously the moon.
If you are still not sure about the date then you can use our Arabic date converter.
The following is the conversion of the Gregorian date 12 March 1966 to its equivalent Arabic date.
The following is the conversion of the Arabic date 20 Dhul Qidah 1385 AH to its equivalent Gregorian date.
فَمَنۢ بَدَّلَهُۥ بَعْدَمَا سَمِعَهُۥ فَإِنَّمَآ إِثْمُهُۥ عَلَى ٱلَّذِينَ يُبَدِّلُونَهُۥٓ ۚ إِنَّ ٱللَّهَ سَمِيعٌ عَلِيمٌۭ
And whoso changeth (the will) after he hath heard it - the sin thereof is only upon those who change it. Lo! Allah is Hearer, Knower.
Surah Al-Baqara(2:181)