javascript - Round moment.js object time to nearest 30 minute interval

Question

I was trying to round the moment.js time object to next nearest 30 minute interval. But looks my logic us wrong.

Ex:

10:13am -> 10:30am
11:45am -> 12:00pm

Here is my current code

start = moment();
minuteReminder = start.minute() % 30;
start.add(minuteReminder, 'minutes');
start.format("D YYYY, h:mm:ss a");

Answer 1

const start = moment('2018-12-08 09:42');
const remainder = 30 - (start.minute() % 30);
 
const dateTime = moment(start).add(remainder, "minutes").format("DD.MM.YYYY, h:mm:ss a");

console.log(dateTime);

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