Ross Ulbricht, who set up and ran online illegal drugs emporium Silk Road, has been sentenced in New York to life imprisonment.
Prosecutors said that his dark website sold more than $US200m of drugs anonymously.
He was found guilty of charges including conspiracy to commit drug trafficking, money laundering and computer hacking.
The site was shut down in 2013 after police arrested Ulbricht.
In February, he was convicted by a federal court in New York of operating the site for nearly three years from 2011.
Users used the online currency Bitcoin to purchase drugs such as heroin, cocaine and LSD.
The untraceable deals earned him at least $18m.
Prosecutors said that six people who died from overdoses bought drugs via the site.
The dark web
The Silk Road was only accessible on the dark web, a part of the internet that requires the specialist software Tor to access.
Tor was created by the US government to help provide activists with anonymity but is now often used to mask illegal transactions.
As well as drugs, the Silk Road also offered hacking equipment and stolen passports.
Prosecutors had sought the heavy sentence as a deterrent.
US District Judge Katherine Forrest told Ulbricht that he was "no better a person than any other drug dealer".
"There must be no doubt that lawlessness will not be tolerated," she told a tearful Ulbricht.
Ulbricht had expressed remorse and had written to the judge begging to not receive a life sentence as it was akin to a death sentence.
"I know you must take away my middle years," he wrote. "but please leave me my old age."