Swift:
Finding the length of a string

How to:

In Swift, you get a string’s length by accessing its count property. Straightforward, let’s do it:

let greeting = "Hello, World!"
print(greeting.count) // Output: 13

Remember that Swift considers emoji as single characters, thanks to Unicode:

let wave = "👋"
print(wave.count)  // Output: 1

Deep Dive

Back in the Objective-C days, string length wasn’t so direct—there was length and lengthOfBytes(using:). Swift made it cleaner with count.

Be aware of composite characters: visually single characters made of multiple Unicode scalars. count handles these gracefully.

Alternatives? Sure, you could traverse the string with a loop, but that’s re-inventing the wheel and less efficient.

Under the hood, count is O(n), where ‘n’ is the number of characters. That’s because Swift’s String is not a collection of Chars, but a sequence of grapheme clusters, which can vary in length.

See Also

• Swift Documentation on Strings: Swift String Docs
• Unicode Basics: Unicode Consortium
• Dive into Swift’s String Performance: Swift String Perf