If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Enter the upper and lower bound below and the program will use a Web Worker to run a background thread to calcular the number of multiples of 3 or 5 between the two numbers, as well as the sum of these numbers.
Web Workers allow for work to be done while leaving the user experience/interface uninterrupted. To illustrate this point, this example includes a loading icon that will display while the calculations are being done in the background.