It was narrated from Abu Hurairah that the Messenger of Allah (ﷺ) said:“Even if there was only one day left of this world, Allah would make it last until a man from my household took possession of (the mountain of) Dailam and Constantinople.”
هـSunan Ibn MajahHadith 4092Da'if (weak)Narrated by It wasسنن ابن ماجهرقم ٤٠٩٢
It was narrated from Mu'adh bin Jabal that the Prophet (ﷺ) said:"The great fierce battle, the conquest of Constantinople and the emergence of Dajjal, will all happen within seven months
Grades by collection
Sahih al-Bukhari451
Sahih Muslim464
Sunan Abi Dawud151
Jami' at-Tirmidhi338
Sunan an-Nasa'i50
Sunan Ibn Majah437
Muwatta Malik8
al-Mustadrak (al-Hakim)627
Musnad Ahmad716
Sunan ad-Darimi21
Kitab al-Fitan (Nu'aym ibn Hammad)1,988
SahihHasanDa'if (weak)Ungraded
Bukhari and Muslim are sahih by inclusion. For the others the bar follows al-Albani's verdict where he graded, then Zubair Ali Zai. Every verdict is on each card.