Round a Date() to the nearest 5 minutes in javascript

Question

Using a Date() instance, how might I round a time to the nearest five minutes?

For example: if it\'s 4:47 p.m. it\'ll set the time to 4:45 p.m.

Answer 1

There is an NPM package @qc/date-round that can be used. Given that you have a Date instance to be rounded

import { round } from '@qc/date-round'

const dateIn = ...; // The date to be rounded
const interval = 5 * 60 * 1000; // 5 minutes
const dateOut = round(dateIn, interval)

Then you can use date-fns to format the date

import format from 'date-fns/format';

console.log(format(dateOut, 'HH:mm')) // 24-hr
console.log(format(dateOut, 'hh:mm a')) // 12-hr

Answer 2

Round to nearest x minutes

Here is a method that will round a date object to the nearest x minutes, or if you don't give it any date it will round the current time.

let getRoundedDate = (minutes, d=new Date()) => {

  let ms = 1000 * 60 * minutes; // convert minutes to ms
  let roundedDate = new Date(Math.round(d.getTime() / ms) * ms);

  return roundedDate
}


// USAGE //

// Round existing date to 5 minutes
getRoundedDate(5, new Date()); // 2018-01-26T00:45:00.000Z

// Get current time rounded to 30 minutes
getRoundedDate(30); // 2018-01-26T00:30:00.000Z