JK Rowling is the world's best-paid author, banking more than £170 million in the last year, according to US business magazine Forbes.

Rowling, who wrote the first of her best-selling books about boy wizard Harry Potter while an impoverished single mother, earned £300m (£170m) over the past year.

The 43-year-old billionaire author's income was six times that of second-placed James Patterson, who wrote Along Came A Spider.

Last month, Rowling donated £1m to the Labour Party ahead of its annual conference, saying her gift was motivated by Labour's record on child poverty and Tory leader David Cameron's offer of tax breaks to married couples.

A Forbes spokesman said: "It was wizardry that transformed JK Rowling from a destitute single mother on welfare into a bestselling billionaire." The magazine described her work as "a children's literary sensation" and a "publishing hit".

It went on: "Once a single mother on welfare, Rowling can now claim best-selling billionaire status thanks to her Harry Potter franchise.

"Over on the big screen, her Potter franchise has already generated £4.5bn (£2.6bn) at the worldwide box office - and she still has three more flicks to come."

The mother of three was presented with the Edinburgh Award last month. She also devotes time and money to various charities including the Multiple Sclerosis Society Scotland, of which she is patron.