Books like Kingdom of Ash
Sarah J. Maas
Kingdom of Ash is 990 pages, about 18 hours 9 minutes at 250 words a minute.
9 books to read next
How long each takes
The Ballad of Never After 7.6 h 
A Blade So Black 7.3 h 
Crier's War 8.4 h Nightbane 7.9 h 
Inheritance 15.3 h 
Ghosts of the Shadow Market 11.4 h 
Crowntide 7.6 h 
The Demon in the Wood 1.3 h 
Sufficiently Advanced Magic 11.4 h Bar height shows length. Estimated at 250 words a minute.