How long did the extreme market plunge last during the 2010 Flash Crash?

The extreme market plunge during the 2010 Flash Crash lasted about 36 minutes.

On May 6, 2010, U.S. stock markets dropped rapidly between roughly 2:32 p.m. and 3:07 p.m. Eastern Time. The Dow Jones Industrial Average briefly lost nearly 1,000 points, while many individual securities displayed extraordinary price movements before much of the decline reversed.

The event exposed the speed and complexity of electronic trading. Investigations concluded that a large automated sell order, combined with high-frequency trading and stressed market liquidity, helped amplify the move. The U.S. Securities and Exchange Commission and Commodity Futures Trading Commission later described the interaction of these factors in their joint report.

The Flash Crash was not a conventional, months-long bear market. It was a short-lived market-structure shock, and many trades executed at extreme prices were later canceled under exchange rules. New safeguards, including circuit breakers for individual stocks and market-wide controls, followed.