I enjoy Hayao Miyazaki and Studio Ghibli movies. I first saw the movie on video and again recently during a Studio Ghibli series by the local independent movie theater. So when my Kindle showed an advertisement to buy this book for $1.99, I jumped at the chance.
In the first quarter, I could tell a few differences. For instance, in the movie Sophie meets Howl when soldiers harass her. In the book Howl is the one doing the harassing. And the differences grow bigger from there. Enough I would consider them different stories.
If you have only watched the movie, then I recommend reading the book. This story is the interesting of the two. Here Howl is a womanizer. Sophie’s development over the course of the story seemed stronger. Michael, the apprentice, actually has a real point to the story. I kind of wish the book version was the movie made.