---
title: Marking API Availability in Objective-C
framework: swift
role: article
role_heading: Article
path: swift/marking-api-availability-in-objective-c
---

# Marking API Availability in Objective-C

Use a macro to denote the availability of an Objective-C API.

## Overview

Overview In Swift, you use the @available attribute to control whether a declaration is available to use when building an app for a particular target platform. Similarly, you use the availability condition #available to execute code conditionally based on required platform and version conditions. Both kinds of availability specifier are also available in Objective-C. For detailed information about specifying and checking platform availability, see available and Checking API Availability in The Swift Programming Language. Mark Availability Use the API_AVAILABLE macro to add availability information in Objective-C: @interface MyViewController : UIViewController - (void) newMethod API_AVAILABLE(ios(11), macosx(10.13)); @end This is equivalent to using the @available attribute on a declaration in Swift: @available(iOS 11, macOS 10.13, *) func newMethod() {     // Use iOS 11 APIs. } Check Availability Use the @available() keyword to check availability information in a conditional statement in Objective-C: if (@available(iOS 11, *)) {     // Use iOS 11 APIs. } else {     // Alternative code for earlier versions of iOS. } This is equivalent to the following conditional in Swift: if #available(iOS 11, *) {     // Use iOS 11 APIs. } else {     // Alternative code for earlier versions of iOS. }

## See Also

### Customizing Objective-C APIs

- [Designating Nullability in Objective-C APIs](swift/designating-nullability-in-objective-c-apis.md)
- [Renaming Objective-C APIs for Swift](swift/renaming-objective-c-apis-for-swift.md)
- [Improving Objective-C API Declarations for Swift](swift/improving-objective-c-api-declarations-for-swift.md)
- [Grouping Related Objective-C Constants](swift/grouping-related-objective-c-constants.md)
- [Making Objective-C APIs Unavailable in Swift](swift/making-objective-c-apis-unavailable-in-swift.md)