Google Parent Alphabet Loses About $500 Billion in a Day, Its Worst Stock Drop Ever

Alphabet, the parent company of Google, lost roughly $500 billion in market value on Thursday, October 29, 2026, after its shares fell 12.6%. It was the stock’s worst one-day drop since the company went public in 2004, and the second-largest single-day loss of market value in US stock market history. The sell-off followed a third-quarter earnings report in which search revenue grew more slowly than analysts expected and free cash flow turned sharply negative.

What Happened on Thursday

Alphabet’s Class A shares closed at $283.82, down 12.64%, according to figures Fox Business attributed to The Wall Street Journal. CNBC reported that the fall passed the stock’s previous worst daily percentage drop, 11.63% in March 2020. In dollar terms, only Nvidia has lost more in a single day, about $589 billion in January 2025, NBC News reported. Alphabet’s own previous record was about $275 billion, on July 23, 2026, according to Yahoo Finance.

The size of the loss depends on who is counting. Fox Business reported about $499.8 billion and NBC News about $500 billion. Yahoo Finance’s own calculation was $482 billion, and BigGo Finance put it near $479 billion. The Nasdaq Composite closed down 1.38%. Microsoft, whose shares had initially risen after its own results, ended the day roughly flat, NBC News reported.

Why the Shares Fell

Alphabet reported its third-quarter results on Wednesday after the market closed. Revenue came to $127.6 billion, up 25% from a year earlier but below Wall Street’s expectations, Fox Business reported.

Search was the main disappointment. Revenue from Google Services, the unit covering search ads, YouTube and subscriptions, reached $96.3 billion against the roughly $98.5 billion analysts expected, Yahoo Finance reported. Search revenue grew 12% year on year, down from 17% in the second quarter and 19% in the first.

The cash figures drew just as much attention. Free cash flow was negative $9.07 billion, against the $2.7 billion shortfall analysts had expected, CNBC reported. Alphabet also kept its full-year capital spending guidance at between $195 billion and $205 billion.

Not all the numbers were weak. Yahoo Finance reported that Google Cloud revenue more than doubled to about $31 billion and that the Gemini app passed one billion users.

The Wider Question About AI Spending

CNBC reported that the drop comes as investors scrutinize how much big tech companies are spending on artificial intelligence and what they are getting back. Mike O’Rourke, chief market strategist at JonesTrading, told The Wall Street Journal that Google “showed vulnerability to AI,” Yahoo Finance reported.

Worry about AI spending has been building for weeks. Global tech stocks fell earlier this month on fears about the AI market, as we reported on October 15. Yahoo Finance counted 18 sessions this year in which a US-listed company lost $200 billion or more in value, before Thursday’s.

Analysts did not agree on what the drop means. Ross Mayfield of Baird Investment said smaller companies outperforming the broader market on the day suggested investors did not see cracks everywhere in the AI trade, BigGo Finance reported.

For readers with money in US index funds, a large company like Alphabet can show up in those funds’ daily moves. Share prices change from one minute to the next, so check a live source for current figures. More in our Business section.

Source: NBC News; CNBC; Fox Business; Yahoo Finance (market value loss, Wall Street reaction); BigGo Finance, published October 29 to 30, 2026.

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