---
title: IOVMPageSize
framework: driverkit
role: symbol
role_heading: Global Variable
path: driverkit/iovmpagesize
---

# IOVMPageSize

The number of bytes in a virtual memory page.

## Declaration

```occ
extern uint64_t IOVMPageSize;
```

## Discussion

Discussion Use this constant in places where you want to specify the size of a virtual memory page.