How to display time ago from a date in Swift (This is how to get the difference between two dates in a string)

How to display time ago from a date in Swift ?

Using Swift 5.1

This is how you can display time ago easily with Swift 5.1:

When iOS13 was released Apple introduce a new class RelativeDateTimeFormatter

1extension Date {
2        func timeAgoDisplay() -> String {
3            let formatter = RelativeDateTimeFormatter()
4            formatter.unitsStyle = .full
5            return formatter.localizedString(for: self, relativeTo: Date())
6        }
7    }

This class will allow you to get a time ago string based on your language. It automatically select the right unit of time based on your interval, here is an example:

1|--------------------------|------------------|
2| Time interval in seconds |      Display     |
3|--------------------------|------------------|
4|             -6           |   6 seconds ago  |
5|            -60           |   1 minute ago   |
6|           -600           |  10 minutes ago  |
7|          -6000           |    1 hour ago    |
8|         -60000           |   16 hours ago   |
9|--------------------------|------------------|

You’ll notice that it handle automatically plurals for you ! So you do not have to care about it. This feature is really useful if you are building a chat for example.

Using Swift 3 or Swift 4

In order to get the number of seconds we need to check if we have one minute or less, you can write that to get the current date minus one minute:

1let minuteAgo = calendar.date(byAdding: .minute, value: -1, to: Date())!

Now we will compare those 2 dates now! (We replace yourDate by self) and get the difference between those 2 dates.

1if (minuteAgo < yourDate) {
2        let diff = Calendar.current.dateComponents([.second], from: yourDate, to: Date()).second ?? 0
3        print("\(diff) sec ago")
4    }

That’s it, you are now about to display time ago in your favorite application

So, the extension is this way: (This is a simple extension for getting the time before)

1extension Date {
2        func timeAgoDisplay() -> String {
3
4            let calendar = Calendar.current
5            let minuteAgo = calendar.date(byAdding: .minute, value: -1, to: Date())!
6            let hourAgo = calendar.date(byAdding: .hour, value: -1, to: Date())!
7            let dayAgo = calendar.date(byAdding: .day, value: -1, to: Date())!
8            let weekAgo = calendar.date(byAdding: .day, value: -7, to: Date())!
9
10            if minuteAgo < self {
11                let diff = Calendar.current.dateComponents([.second], from: self, to: Date()).second ?? 0
12                return "\(diff) sec ago"
13            } else if hourAgo < self {
14                let diff = Calendar.current.dateComponents([.minute], from: self, to: Date()).minute ?? 0
15                return "\(diff) min ago"
16            } else if dayAgo < self {
17                let diff = Calendar.current.dateComponents([.hour], from: self, to: Date()).hour ?? 0
18                return "\(diff) hrs ago"
19            } else if weekAgo < self {
20                let diff = Calendar.current.dateComponents([.day], from: self, to: Date()).day ?? 0
21                return "\(diff) days ago"
22            }
23            let diff = Calendar.current.dateComponents([.weekOfYear], from: self, to: Date()).weekOfYear ?? 0
24            return "\(diff) weeks ago"
25        }
26    }

This class is very straightforward to use, here is an example:

1var now = Date()
2    now.timeAgoDisplay()

That’s it you can now display time ago in your chat application. I’ve made this post based on an stackoverflow answer that I wrote here

How to display time ago from a date in Swift (This is how to get the difference between two dates in a string)