---
title: blockSize
framework: fskit
role: symbol
role_heading: Instance Property
path: fskit/fsblockdeviceresource/blocksize
---

# blockSize

The logical block size, the size of data blocks used by the file system.

## Declaration

```swift
var blockSize: UInt64 { get }
```

## Discussion

Discussion This is equivalent to the DKIOCGETBLOCKSIZE device parameter.

## See Also

### Accessing resource properties

- [bsdName](fskit/fsblockdeviceresource/bsdname.md)
- [isWritable](fskit/fsblockdeviceresource/iswritable.md)
- [blockCount](fskit/fsblockdeviceresource/blockcount.md)
- [physicalBlockSize](fskit/fsblockdeviceresource/physicalblocksize.md)