Abdul Elahi was described as being “in a league of his own” in terms of the scale of his online offending.
Some women were blackmailed into abusing a baby or a sibling, with Elahi offering to pay off their debts.
Elahi, 26, formerly of Allcroft Road, Sparkhill, Birmingham, is due to be sentenced later.
He previously admitted 158 charges committed against 72 complainants.
It is believed he tried to exploit victims in 34 countries, with more than 500 from the UK and almost 2,000 identified altogether in the UK and US.
At the start of the sentencing hearing at Birmingham Crown Court on Wednesday, it was said Elahi juggled many potential victims at any one time, using a fake persona to pose as a wealthy stockbroker offering financial assistance.
The prosecution called him an “exceptionally dangerous predator.”
“The whole persona, the whole arrangement, was a sham from the very beginning,” prosecutor Adrian Langdale QC said.
“He simply, it would appear, saw his victims as a way of making money. Victims were targeted day after day, with no let-up from Mr Elahi.”
Elahi also “acted as a mentor” to other online abusers, the court heard, with “copy-cat” offenders targeting some of his victims.
So-called “box sets” of abusive images and videos compiled by Elahi were distributed in vast quantities, the court heard, after girls and young adults were blackmailed into providing humiliating and degrading sexual material.
Mr Langdale said Elahi had switched online conversations to WhatsApp to cover his tracks, adding: “Sixty-seven thousand indecent images of children have been recovered from numerous devices and cloud storage for Elahi.”
Evidence suggested he “carefully structured and logged all of his material,” the court heard, as the offending spanned a three-year period from 2017 to 2019.
The pictures were sold on irrespective of the damage he was causing, the court was told.
Among those targeted on so-called “sugar daddy” websites were financially desperate victims, including mothers at risk of losing their homes or struggling to feed their children.
During the offending, the court heard, Elahi was living in his family home and his only legitimate income was from working for a short period in a branch of McDonald’s.
Mr Langdale said: “As he was eventually to admit… he said this was a full-time career and occupation.”