Alphabet shares fell 8% on Wednesday as investors balked at the Google parent's slowing cloud growth and planned $75 billion capital spending for the year, underscoring growing fears over Big Tech's escalating artificial intelligence costs.

Alphabet shares dropped after the search giant fell short of Wall Street's fourth-quarter revenue expectations and announced big spending plans

Alphabet's fourth-quarter earnings day is here, with numbers expected to be released after the markets close Tuesday. This will be followed by an earnings call at roughly 4:30 p.m. ET. The stock has been riding high over the past month as investors grew bullish over Google's AI investment.

Alphabet reports fourth-quarter earnings after Tuesday's closing bell. Investors will be focused on cloud momentum and AI traction, with shares of the Google and YouTube parent company holding fast near the record levels achieved last week.

Google parent Alphabet (GOOGL) reported fourth-quarter earnings that topped analysts' estimates, but its cloud revenue came in short, sending shares lower in extended trading Tuesday. The tech giant saw revenue grow 12% year-over-year to $96.