Well, the Hijri date 15 Jumada Al Akhira 1256 corresponds to the Gregorian date Thursday, 13 August 1840. This date lies in the sixth month of the Hijri year 1256 AH, which is Jumada Al-Thani of 1256 AH. Both this Hijri and Gregorian date occur on the single day that is Thursday without any doubt. The Arabic date 1256/06/15 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 13 August 1840 to its equivalent Arabic date.
The following is the conversion of the Arabic date 15 Jumada Al Akhira 1256 AH to its equivalent Gregorian date.
۞ وَٱتْلُ عَلَيْهِمْ نَبَأَ نُوحٍ إِذْ قَالَ لِقَوْمِهِۦ يَٰقَوْمِ إِن كَانَ كَبُرَ عَلَيْكُم مَّقَامِى وَتَذْكِيرِى بِـَٔايَٰتِ ٱللَّهِ فَعَلَى ٱللَّهِ تَوَكَّلْتُ فَأَجْمِعُوٓا۟ أَمْرَكُمْ وَشُرَكَآءَكُمْ ثُمَّ لَا يَكُنْ أَمْرُكُمْ عَلَيْكُمْ غُمَّةًۭ ثُمَّ ٱقْضُوٓا۟ إِلَىَّ وَلَا تُنظِرُونِ
Recite unto them the story of Noah, when he told his people: O my people! If my sojourn (here) and my reminding you by Allah's revelations are an offence unto you, in Allah have I put my trust, so decide upon your course of action you and your partners. Let not your course of action be in doubt for you. Then have at me, give me no respite.
Surah Yunus(10:71)