A computer storage device having a host interface, a controller, non-volatile storage media, and firmware. The firmware instructs the controller to select a block size for allocating blocks to namespaces based on a storage capacity of the non-volatile storage media. Various requests by a host to create namespaces are received by the controller via the host interface. After each request is received, the controller allocates blocks to the requested namespace using the selected block size. The controller can select the block size at the time of initial manufacture or operation, and/or can dynamically select various block sizes during operation of the storage device. Dynamic selection of the block size can be based on signaling from sensors of the storage device and/or host.