How to Make a POST Request with URLSession

Send JSON data in a POST request.

Steps

Paste the code into a Swift file or playground.
Run it once to verify the output.
Adjust the inputs to match your use case.

Copy and paste

import Foundation

let url = URL(string: "https://api.example.com/login")!
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.setValue("application/json", forHTTPHeaderField: "Content-Type")

let payload = ["email": "[email protected]", "password": "secret"]
request.httpBody = try JSONSerialization.data(withJSONObject: payload)

let task = URLSession.shared.dataTask(with: request) { data, response, error in
    if let error = error {
        print("Error:", error)
        return
    }
    print("Success")
}

task.resume()

Notes

Keep functions small and focused for reuse.
Prefer safe APIs like optionals and guards.