---
title: "CFNumberGetByteSize(_:)"
framework: corefoundation
role: symbol
role_heading: Function
path: "corefoundation/cfnumbergetbytesize(_:)"
---

# CFNumberGetByteSize(_:)

Returns the number of bytes used by a CFNumber object to store its value.

## Declaration

```swift
func CFNumberGetByteSize(_ number: CFNumber!) -> CFIndex
```

## Parameters

- `number`: The CFNumber object to examine.

## Return Value

Return Value The size in bytes of the value contained in number.

## Discussion

Discussion Because a CFNumber object might store a value using a type different from that of the original value with which it was created, this function may return a size different from the size of the original value’s type.

## See Also

### Getting Information About Numbers

- [CFNumberGetType(_:)](corefoundation/cfnumbergettype(_:).md)
- [CFNumberGetValue(_:_:_:)](corefoundation/cfnumbergetvalue(_:_:_:).md)
- [CFNumberIsFloatType(_:)](corefoundation/cfnumberisfloattype(_:).md)