The court had been told that the teenager, from Liverpool, had been forced to act as a drugs trafficker.
The schoolboy had admitted selling drugs to undercover police officers.
The boy, who is now 15, was dubbed the Kinder Egg dealing kid after he hid his drugs in a children's chocolate egg.
He has been ordered to remain in local authority care until he is sentenced.
Judge Stephen Clarke also warned that custody was normal in such cases, he said: "He must understand that all sentencing options remain open.
He is 15. The court has to have in mind a custodial sentence."
Drug deals
Earlier in the trial the the court heard that the schoolboy feared for his life when he agreed to deal in hard drugs for a drugs gang in Rhyl.
But the jury was told that he used all the drug dealing terms, took instructions on a mobile phone, was driven by others to do some of the deals - and even drove himself on at least one occasion.
The court heard how he had ended up selling the drugs to police officers on five occasions.
The boy agreed that he had done everything that the police alleged but his lawyers argued that he had been forced to do it and put forward a defence of duress.
His barrister Gwyn Price Rowlands told the jury that his client had gone on a week's holiday to Rhyl with a drugs dealer from Liverpool.
Mr Rowlands claimed that the boy had been threatened with violence and forced to sell drugs on the man's behalf.
Andrew Thomas, prosecuting dismissed the claim of duress.
Sentence
He said: "He was a trusted member of a criminal gang, trusted with the drugs, trusted with the cash, trusted with the mobile telephone and trusted with the car.
"Why should the dealer go to so much trouble, expense and take the risk of kidnapping a boy to deal drugs for him when there were sadly plenty of others who would do it for drugs or money?"
The jury rejected the defences claims and took the view that teenager had acted voluntarily.
He will be sentenced at a later date together with two men who drove him on occasions, who have already admitted their part in the drugs supply, and who are currently in custody.