The hip-hop artist's fortune now "conservatively tops $1bn" (£792m), according to a new report released by Forbes on Monday.
Just two years ago, the magazine presented Jay-Z and Diddy as being "locked in a battle" in the race to accumulate their first billion.
Per Forbes's estimates, Jay-Z's wealth is bolstered by ventures such as his champagne brand Armand de Brignac (worth an estimated $310m/£245m) and the subscription-based content-sharing platform Tidal (with an estimated worth of $100m/£79m).
Another contributing factor is the rapper's reported "cash and investments", which total an estimated $200m (£158m).
His music catalog adds an estimated $75m (£59m).
In 2017, Jay-Z came second in Forbes's ranking of the world's five richest rappers, with an estimated net worth of $810m (£641m). Diddy occupied the first spot with $820m (£650m).
Dr Dre came third with $740m (£586m), followed by Birdman ($110m/£87m) and Drake ($90m/£71m).
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