The Roundhill Magnificent Seven ETF — which holds Big Tech stocks including Nvidia, Apple Inc., Microsoft Corp, Alphabet Inc., Amazon.com Inc., Tesla Inc. and Meta Platforms Inc. —was up 1.5% in afternoon trading, according to FactSet data, at last check. Nvidia was rallying the most with a 3.8% jump, followed by Tesla at 1.8% and Apple at 1.5%.

Major Indexes are poised to open higher Tuesday, recovering from the previous session's selloff, as investors await key economic data and earnings reports in the coming days.

A key stock market index in Hong Kong saw the biggest single-day drop since the financial crisis on Tuesday. The Hang Seng index fell by -2172.99 (-9.41 percent) on Tuesday.

Chinese shares soared to two-year highs in frenzied trade on Tuesday, extending a blistering rally as mainland markets reopened after a week-long break, while Hong Kong shares slid as investors walked back some of the stimulus excitement.

China's Weibo microblog was abuzz with discussions about the stock market rally a day before they reopen following weeklong National Day holidays.