According to Our World in Data, 2019:
The area of global land allocated for raising livestock and feed is equivalent to North, Central, and South America combined.
According to a 2018 paper published in Science, a vegan diet reduces land use by 76%. As an added benefit, veganic farming techniques (which use plant compost rather than manure) further improve soil quality and reduce water pollution.
Get the long read in this excellent Guardian article.