How it works

Reading order

Series and their order come from Wikidata, the open database behind Wikipedia, which records which books belong to a series and their position in it. When Wikidata lists two editions under the same position, we keep the better-documented one. Reading order follows the series' own numbering, which is usually publication order.

Reading time

We assume 275 words a page and a pace of 250 words a minute, the average for an adult reading for pleasure. Page counts are the median across editions on Open Library, so your copy may differ. The book pages show the time at five different speeds.

Free books

A book is marked free when it's in the public domain and on Project Gutenberg or the Internet Archive. "Borrow free" means Open Library lends a scanned copy to one reader at a time. Free audiobooks are LibriVox recordings by volunteers. We check each source, but availability can change, especially for borrowing.

Prices and money

We don't quote prices, because no used-book shop publishes them in a way we could verify every day. We link to ThriftBooks, AbeBooks, Better World Books and Bookshop.org and earn a small commission if you buy. Commission never affects which books appear or in what order.

Sources