Madihah Taheer was convicted of preparing to commit terrorist acts after Woolwich Crown Court in London was told she also bought Ummariyat Mirzaa martial arts dummy so he could practice stabbing techniques.
The couple, who fell in love as teenagers, were inspired by Islamic State (ISIS) propaganda and had initially wanted to travel to Syria to join the terrorist network but stayed in the UK to plot an attack in their hometown of Birmingham instead.
Mirza, a former accountant,had also been aided by his 23-year-old sister Zainub, who had earlier pleaded guilty to encouraging the plot by sharing graphic ISIS videos and propaganda, including footage showing hostages being beheaded and drowned.
"Mirza's plan was escalating quickly so the decision to carry out arrests in a busy Birmingham street at rush hour was not taken lightly," said Detective Chief Inspector Matt Ward, head of the West Midlands Counter Terrorist Unit, in reference to Mirza's arrest.
More From This Section
Mirza had already pleaded guilty to planning a knife attack after being arrested by armed police in March, but his wife had denied knowledge of the plot.
The court was told that Taheer, who was pregnant at the time, squabbled with her husband on WhatsApp about the cost of the knife he wanted to buy, saying all knives "do the same thing".
Taheer also allowed her debit card to be used to buy a plastic knife and a life-like martial arts dummy so that her husband could practice the attack, the court was told.
The jury was told that Taheer and Mirza had boasted to each other about their extremist views and discussed how they would celebrate their marriage by carrying out an attack.
In one exchange between the couple before marriage, Mirza wrote: "The day of nikkah [wedding], I'll kill em all. Give me the list, the only thing that stops me is we are not married. I will defo, I'm not joking."
Mirza was arrested just days after an ISIS-inspired terrorist attack on the UK Parliament complex in London by Khalid Masood that claimed four lives and injured scores others.
All three will be sentenced by the end of the year.