JavaScript Program: Repeatedly executing a function at fixed intervals using setInterval()

JavaScript Asynchronous: Exercise-8 with Solution

Write a JavaScript program to implement a function that executes a given function repeatedly at a fixed interval using 'setInterval()'.

Sample Solution:

JavaScript Code:

function repeat_Function(fn, interval) {
  // Execute the function immediately
  // Set up the interval to execute the function repeatedly
  const intervalId = setInterval(fn, interval);
  // Return a function to stop the execution
  return function stopExecution() {
    console.log('Execution stopped.');
// Usage example:
const intervalMs = 1000; // 1 second
// Define the function to be repeated
function printMessage() {
  console.log('Executing the function...');
// Start the repeated execution
const stopExecution = repeat_Function(printMessage, intervalMs);
// Stop the execution after 4 seconds
setTimeout(() => {
}, 4000);


"Executing the function..."
"Executing the function..."
"Executing the function..."
"Executing the function..."
"Executing the function..."
"Execution stopped."

Note: Executed on JS Bin


In the above exercise -

  • The "repeatFunction()" function takes two parameters: fn represents the function to be executed repeatedly, and interval specifies the time interval (in milliseconds) between each execution.
  • Inside repeatFunction, the provided function fn is executed immediately to ensure it runs before starting the interval.
  • 'setInterval' is used to set up repeated execution. The returned intervalId is stored to clear the interval if needed.
  • The function returns another function (stopExecution) that stops execution when called. This function clears the interval using clearInterval and logs a message indicating that execution has stopped.

In the example, a time interval of 1 second (1000 milliseconds) is specified. The "printMessage()" function is defined to log a message, and repeatFunction is called to start repeated execution. After 4 seconds (4000 milliseconds), the stopExecution function is invoked to stop execution.


Flowchart: Repeatedly executing a function at fixed intervals using setInterval().

Live Demo:

See the Pen javascript-asynchronous-exercise-8 by w3resource (@w3resource) on CodePen.

Improve this sample solution and post your code through Disqus.

Asynchronous Exercises Previous: JavaScript Function for Retrying API Requests with Automatic Retry.
Asynchronous Exercises Next: Fetching data from API with request timeout.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.

Follow us on Facebook and Twitter for latest update.