I recently finished it and was surprised by the length. The full audiobook for 'Boundless' runs just over 22 hours. I clocked mine at 22 hours and 7 minutes, though I've seen some listings round it to 22 hours even. That's a serious commitment compared to a lot of contemporary fiction audiobooks, which often land in the 8-12 hour range.
It's a marathon, not a sprint, and the pacing reflects that. There were stretches, especially in the middle with the more philosophical world-building, where I had to slow my listening speed just to absorb everything. It’s not a book you can casually half-listen to while multitasking; it demands attention. I found it worked best during long drives or dedicated evening sessions. The narrator’s performance is a big part of it—they take their time with the dialogue and the dense descriptive passages, which adds to the overall runtime but also to the atmosphere.
Honestly, whether that length feels rewarding really depends on what you're after. If you loved the intricate details and slow-unfolding mystery of the book, every minute feels necessary. If you were more into the core plot, some sections might drag. For me, the length became part of the experience, making the ending feel earned after such a long journey.