The average size of a poetry book can vary quite a bit, depending on the type of poetry included in the book and the format of the book itself. Generally, traditional poetry books come in three different sizes - small, medium, and large. The most common size for a poetry book is between 80 and 90 pages, with smaller books generally having around 50 pages and larger books having upwards of 150 pages. However, if the book contains multiple types of poetry, such as illustrations, notes, and commentaries, it could be a larger book. Additionally, if the book is presented in a larger format (such as an oversized book with a hardcover), it too could be a larger book. Ultimately, there is no ‘one-size-fits-all’ answer when it comes to the average size of a poetry book.