How do I see which version of Swift I’m using?

I just created a new Swift project within Xcode. I am wondering which version of Swift it’s using.

How can I see, in Xcode or the terminal, what version of Swift I am using inside my project?

Project build settings have a block ‘Swift Compiler – Languages’, which stores information about Swift Language Version in key-value format. It will show you all available (supported) Swift Language Version for your Xcode and active version also by a tick mark.

Project ► (Select Your Project Target) ► Build Settings ► (Type
‘swift_version’ in the Search bar) Swift Compiler Language ► Swift Language
Version ► Click on Language list to open it (and there will be a tick mark on any one of list-item, that will be current swift version).

Look at this snapshot, for easy understanding:

With help of following code, programmatically you can find Swift version supported by your project.

#if swift(>=5.3)
print("Hello, Swift 5.3")

#elseif swift(>=5.2)
print("Hello, Swift 5.2")

#elseif swift(>=5.1)
print("Hello, Swift 5.1")

#elseif swift(>=5.0)
print("Hello, Swift 5.0")

#elseif swift(>=4.2)
print("Hello, Swift 4.2")

#elseif swift(>=4.1)
print("Hello, Swift 4.1")

#elseif swift(>=4.0)
print("Hello, Swift 4.0")

#elseif swift(>=3.2)
print("Hello, Swift 3.2")

#elseif swift(>=3.0)
print("Hello, Swift 3.0")

#elseif swift(>=2.2)
print("Hello, Swift 2.2")

#elseif swift(>=2.1)
print("Hello, Swift 2.1")

#elseif swift(>=2.0)
print("Hello, Swift 2.0")

#elseif swift(>=1.2)
print("Hello, Swift 1.2")

#elseif swift(>=1.1)
print("Hello, Swift 1.1")

#elseif swift(>=1.0)
print("Hello, Swift 1.0")

#endif

Here is result using Playground (with Xcode 11.x)