The ratio of fiction to non-fiction is the first thing to assess on any shelf. It splits readers into two fundamentally different types before you even read a single title.

Mostly non-fiction

A shelf dominated by non-fiction points to an analytical, information-driven reader. These are people who read to learn, not to escape. They tend to be older, professionally established, and often work in fields where knowledge is a tool — research, consulting, engineering, academia.

Mostly fiction

Fiction-heavy shelves belong to narrative thinkers. They're drawn to story, character, and imagination. They tend to be more emotionally intuitive and often work in creative or people-facing fields.

Mixed shelves

A roughly equal split is actually the most common pattern and the hardest to read. Look at which non-fiction topics dominate — that's where the real signal is.