ISIS wannabes are so ignorant about the culture they’re pledging their lives to that they are ordering books like “Islam for Dummies” before joining the terrorist organization.

About 70 percent of ISIS recruits only have “basic” knowledge of Shariah law, the Islamic legal system, according to an analysis by The Associated Press of more than 3,000 internal documents from the terror network.

Some jihadis-in-training admitted in court that they tried to beef up their knowledge about the religion before traveling to Syria by buying a few books from Amazon.

Convicted terrorists Mohammed Ahmed and Yusuf Sarwar, 22-year-old recruits from Britain, ordered “The Koran for Dummies” and “Islam for Dummies” before their trip.

They were arrested and convicted of terrorism-related charges when they tried to re-enter Britain in 2014.

And prominent Islamic scholars like Mohammed Abdelfadel, who monitors ISIS’ propaganda at Egypt’s Al-Azhar University, said the terror group itself violates many Islamic laws including killing of innocent civilians and engaging in terrorism.

In fact, a study released by the US Military Academy’s Combating Terrorism Center found that ISIS members “with the most religious knowledge within the organization itself are the least likely to volunteer to be suicide bombers.”

“The people who are doing this are not experiencing martyrdom, they are criminals,” said Tariq Ramadan, who teaches Islamic Studies at Oxford University. “They are killing innocent people. Nothing in Islam, nothing ever can justify the killing of innocent people. Never, ever.”

Several ISIS recruits admitted they had no idea what they were getting themselves into when they joined the group.

“It only required one prayer and no prior understanding of Islam,” a gay European newbie told the AP. “There was no hierarchy and it was all about living a good life.”

He added, “People like me were tricked into something that they didn’t understand. I never meant to end up with IS[IS].”

Another 32-year-old European ISIS rookie thought he was becoming a member of a group that was aiding Syrians in their fight against President Bashar Assad.

“I realized that I was in the wrong place when they began to ask me questions on these forms like, ‘When you die, who should we call?’” he said.