How long did the sharpest phase of the 2010 Flash Crash last before markets rapidly recovered?

The sharpest phase of the 2010 Flash Crash lasted about 36 minutes before markets rapidly recovered.

On May 6, 2010, major US stock indexes suddenly plunged and then rebounded during the same afternoon. The Dow Jones Industrial Average temporarily lost nearly 1,000 points, about 9%, before recovering much of the decline. The episode demonstrated how automated trading could transmit stress through many markets at extraordinary speed.

Investigations by US regulators found that a large sell order in E-mini S&P 500 futures interacted with high-frequency trading and liquidity conditions. Trading systems withdrew or changed quotes, while some transactions occurred at extremely unusual prices. Regulators later described the event as a rapid, self-reinforcing market disruption rather than a normal, gradual sell-off.

The crash led to new safeguards, including market-wide circuit breakers and rules for canceling clearly erroneous trades. “36 minutes” refers to the dramatic plunge and recovery period, not the entire trading day. Some individual securities experienced deeper or stranger temporary price moves than the major indexes.