# format(_:) Formats an integer, using this style. ``` func format(_ value: Value) -> String ``` ## Parameters `value` The integer to format. ## Return Value A string representation of `value`, formatted according to the style’s configuration. ## Discussion Use this method when you want to create a single style instance and use it to format multiple integers. The following example creates a style that uses the `en_US` locale, and adds the [`compactName`](/documentation/Foundation/NumberFormatStyleConfiguration/Notation/compactName) modifier. It applies this style to all the integers in an array. ```swift let compactNameStyle = IntegerFormatStyle( locale: Locale(identifier: "en_US")) .notation(.compactName) let nums = [100, 1000, 10000, 100000, 1000000] let formattedNums = nums.map { compactNameStyle.format($0) } // ["100", "1K", "10K", "100K", "1M"] ``` To format a single integer, use the instance method , passing in an instance of [`IntegerFormatStyle`](/documentation/Foundation/IntegerFormatStyle), or to use a default style. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)