Amazon’s Alexa is undergoing its biggest overhaul since debuting more than a decade ago.

On Wednesday, Amazon said it was giving Alexa a new brain powered by generative artificial intelligence. The update, called Alexa+, is set to make the virtual assistant more conversational and helpful in booking concert tickets, coordinating calendars and suggesting food to be delivered. Alexa+ will cost $19.99 a month or be included for customers who pay for Amazon’s Prime membership program. It will roll out next month.

“Until right this moment, right this moment, we have been limited by the technology,” Panos Panay, the head of Amazon’s devices, said at a media event. “Alexa+ is that trusted assistant that can help you conduct your life and your home.”

With the changes, Amazon is aiming to catch up in generative A.I. for everyday users. While the Seattle-based company has in recent months made up for lost time in A.I. products and services that it sells to businesses and other organizations, its grip on consumer A.I. products has been narrower. Alexa’s upgrades, which were first teased in 2023, are Amazon’s biggest bet on becoming a force in consumer A.I.

The moves are also an opportunity to reboot Alexa, which has been perceived as having fallen behind other virtual assistants. In recent years, Alexa’s growth in the United States has generally stagnated, according to the research firm Consumer Intelligence Research Partners, with people turning to the assistant for only a few main tasks, such as setting timers and alarms, playing music and asking questions about the weather and sports scores.

At Wednesday’s event, Mr. Panay and other Amazon executives demonstrated how Alexa+ could do those things in a more personalized manner. Alexa+ could identify who was speaking and know their preferences, such as favorite sports teams, musicians and foods, they said. They also showed how a device powered by Alexa+ could suggest a restaurant, book a reservation on OpenTable, order an Uber and send a calendar invite.