---
title: bitWidth
framework: swift
role: symbol
role_heading: Instance Property
path: swift/staticbigint/bitwidth
---

# bitWidth

Returns the minimal number of bits in this value’s binary representation, including the sign bit, and excluding the sign extension.

## Declaration

```swift
var bitWidth: Int { get }
```

## Discussion

Discussion The following examples show the least significant byte of each value’s binary representation, separated (by an underscore) into excluded and included bits. Negative values are in two’s complement. -4 (0b11111_100) is 3 bits. -3 (0b11111_101) is 3 bits. -2 (0b111111_10) is 2 bits. -1 (0b1111111_1) is 1 bit. +0 (0b0000000_0) is 1 bit. +1 (0b000000_01) is 2 bits. +2 (0b00000_010) is 3 bits. +3 (0b00000_011) is 3 bits.