Swift Dictionary capacity

The capacity property returns the number of elements of the dictionary without allocating any additional storage.


var languages = ["Swift": 2012, "C": 1972, "Java": 1995]

// count total number of elements in languages var result = languages.capacity
print(result) // Output: 3

capacity Syntax

The syntax of the dictionary capacity property is:


Here, dictionary is an object of the Dictionary class.

capacity Return Values

The capacity property returns the total number of elements present in the dictionary without allocating any additional storage.

Example 1: Swift Dictionary capacity

var nameAge = ["Alcaraz": 18, "Sinner": 20, "Nadal": 34]

// capacity total elements on names print(nameAge.capacity)
var employees = [String: String]()
// capacity total elements on employees print(employees.capacity)



In the above example, since

  • nameAge contains three key/value pairs, the property returns 3.
  • employees is an empty dictionary, the property returns 0.

The capacity property here returns a total number of elements without allocating new storage.

Example 2: Using capacity With if...else

var employees = ["Sabby": 1001, "Patrice": 1002, "Ranjy": 1003 ]

// true because there are only 3 elements in employees if (employees.capacity < 5) {
print("Small Company") } else { print("Large Company") }


Small Company

In the above example, we have created the dictionary named employees with 3 key/value pairs.

Here, since there are 3 key/value pairs in the dictionary, numbers.capacity < 5 evaluates to true, so the statement inside the if block is executed.

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