Trader works on the floor of the NYSE in New York
A trader works on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., July 26, 2022.

A strong outlook from Microsoft Corp and resilient Google ads sales from Alphabet sparked a relief rally on Wednesday in heavyweight technology and growth shares that have powered the stock market for the past decade.

Better-than-expected Google ad sales sent Alphabet shares 3.5% higher in premarket trading as the largest online ads seller appeared better positioned to withstand a recession compared to smaller rivals.

Microsoft rose 3.8% after the company said it targets double-digit growth in fiscal revenue, easing worries about the impact of soaring prices and slowing growth, even as it missed estimates for fourth-quarter results.

"Both tech giants (Alphabet and Microsoft) just missed on earnings, but both maintained very upbeat outlooks; that was enough for the FOMO gnomes," said Jeffrey Halley, analyst at Oanda, explaining the motivation behind the rally.

All eyes will now be on ad revenue at Facebook owner Meta Platforms due later in the day after disappointing results from Twitter Inc and Snapchat's owner Snap Inc last week sparked a selloff in social media and ad tech firms.

"The fact that Google has bucked the trend of lower spending on advertising business - which has impacted the likes of Twitter and Snap - suggests the economic outlook may not be quite so bleak as many are anticipating," said Stuart Cole, head macroeconomist at Equiti Capital.

Meta shares rose 2.4%, while Apple Inc and Inc, which are slated to post reports on Thursday, firmed 2.5% and 2%, respectively.

That would conclude results from the largest U.S. firms - Apple, Microsoft, Alphabet and Amazon - which together account for nearly a quarter of the weight in the benchmark S&P 500 index.

An interest rate decision by the Federal Reserve later in the day will be pivotal for rate-sensitive growth stocks. The central bank is expected to raise rate by 75 basis points.