Long-running series are counted here by the number of books listed on each series page in the GoBookSeries index. The counts include companion volumes, novellas and collections that the index groups with the main series.
The 30 Longest Series in the Index
- Forgotten Realms — 281 books · 1987–2023
- Rainbow Magic — 203 books · 2003–2018
- DragonLance — 195 books · 1984–2024
- Sweet Valley High — 180 books · 1977–2012
- Star Trek — 173 books · 1967–2026
- Geronimo Stilton — 157 books · 2000–2022
- Doctor Who — 135 books · 1990–2020
- Nancy Drew — 124 books · 1930–2018
- Goosebumps — 111 books · 1991–2024
- Star Trek: The Next Generation — 95 books · 1987–2017
- The Warriors — 93 books · 2003–2024
- Star Trek: The Original Series — 92 books · 1981–2017
- The Hardy Boys — 90 books · 1927–2019
- Fear Street — 85 books · 1989–2019
- Baby-Sitters Club — 81 books · 1986–2025
- My Weird School — 81 books · 2004–2026
- Star Trek: Deep Space Nine — 74 books · 1993–2017
- Horrible Histories — 64 books · 1993–2025
- Tom Swift — 64 books · 1910–2022
- Animal Ark — 62 books · 1994–2019
- Choose Your Own Adventure — 60 books · 1979–2010
- Sherlock Holmes — 60 books · 1883–1926
- Valdemar — 60 books · 1986–2026
- Dan "Spider" Shepherd — 55 books · 2004–2023
- Ring of Fire — 55 books · 2000–2024
- The X-Files — 51 books · 1994–2017
- Black Ocean — 50 books · 2014–2024
- Dragon's Gift Universe — 49 books · 2016–2021
- Dune — 49 books · 1965–2024
- Montgomery Ink — 49 books · 2013–2025
How the count is worked out
Every book attached to a series page counts once, whether it is a full novel, a novella, an anthology contribution or a companion volume. That is why tie-in and shared-world series appear alongside single-author series in the list above.
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