I have a date in format dd.MM.yyyy HH:mm:ss and I need to convert it to ISO format, but it's not working correctly. Here is my code:

let date = '12.01.2016 0:00:00'; //12 January 2016
let parsedDate = moment(date, 'dd.MM.yyyy HH:mm:ss')
console.log(parsedDate.toISOString()); //result is 2016-12-31T23:00:00.000Z

example2:

let date = '12.01.2016 0:00:00'; //12 January 2016
let parsedDate = new Date(date)
console.log(parsedDate.toISOString()); //result is 2016-11-30T23:00:00.000Z

Where is the problem? Why do I get different results?

I have a date in format dd.MM.yyyy HH:mm:ss and I need to convert it to ISO format, but it's not working correctly. Here is my code:

let date = '12.01.2016 0:00:00'; //12 January 2016
let parsedDate = moment(date, 'dd.MM.yyyy HH:mm:ss')
console.log(parsedDate.toISOString()); //result is 2016-12-31T23:00:00.000Z

example2:

let date = '12.01.2016 0:00:00'; //12 January 2016
let parsedDate = new Date(date)
console.log(parsedDate.toISOString()); //result is 2016-11-30T23:00:00.000Z

Where is the problem? Why do I get different results?

• javascript
• datetime
• momentjs
• datetime-parsing

• Think about the timezone you're in vs GMT. For me, someone living in the GMT timezone, this code works correctly. --- The second example, the first reports the wrong year. – evolutionxbox Commented Oct 25, 2017 at 11:43

4 Answers 4

Your format parameter is wrong, use 'DD.MM.YYYY H:mm:ss' instead.

There is no lowercase dd, use uppercase DD for day of month and use uppercase YYYY for year instead of lowercase yyyy.

Please note that toISOString():

Note that .toISOString() always returns a timestamp in UTC, even if the moment in question is in local mode. This is done to provide consistency with the specification for native JavaScript Date .toISOString(), as outlined in the ES2015 specification.

let date = '12.01.2016 0:00:00'; //12 January 2016
let parsedDate = moment(date, 'DD.MM.YYYY H:mm:ss')
console.log(parsedDate.toISOString());

<script src="https://cdnjs.cloudflare./ajax/libs/moment.js/2.19.1/moment.min.js"></script>

I just tried using moment.js and it seems you used a mask as you'd use in C# for example. Moment.js uses capitals in the date parts.

let date = '12.01.2016 0:00:00'; //12 January 2016
let parsedDate = moment(date, 'DD.MM.YYYY HH:mm:ss');
console.log(parsedDate.toISOString()); //result is 2016-01-11T23:00:00.000Z

The Date.parse() function requires another kind of input.

Look this link https://www.w3schools./js/js_date_formats.asp , paragraph 'ISO Dates'

Omitting T or Z in a date-time string can give different result in different browser.

In the second example, the parsed date results in December 1, 2016 0:00:00 (GMT+1)

When you output toISOString() it gives you the GMT time, which is 1 hour earlier, hence the November 30, 2016 23:00:00