Allah describes it as "a Day the extent of which is fifty thousand years" (Quran 70:4), and the Prophet ﷺ used the same measure when he described the one who withheld the zakat of his gold and silver being dealt with "during a day the extent of which would be fifty thousand years, until judgment is pronounced among the servants" (Sahih Muslim 987). Another verse mentions a day whose measure is a thousand years (Quran 32:5); the scholars reconcile these by saying the verses describe different affairs and stages of that Day, or that its length is experienced differently by different people. What is certain is that its length and severity vary according to a person's deeds and Allah's mercy, and that Allah lightens it for whom He wills.
Evidence — the daleel
On deen2u
Informational, not a personal fatwa. Consult a qualified scholar for rulings on your situation.