The Midnight Library by Matt Haig is a novel that can be enjoyed at different speeds. Some readers may choose to power through the book in a few sittings, while others may want to take their time and savor the experience. There is no right or wrong way to read the book, and everyone's mileage may vary. However, based on the average reading speed, it would take most readers between 8 and 10 hours to finish The Midnight Library.