JavaScript - format current date to yyyy-mm-dd (Iso 8601)

// output format: yyyy-mm-dd

function getDateInFormat_yyyy_mm_dd() {

    function toString(text, padLength) {

        return text.toString().padStart(padLength, '0');

    }

​

    let date = new Date();

​

    let dateTimeNow =

        toString( date.getFullYear(),  4 )

        + '-'  + toString( date.getMonth() + 1, 2 )

        + '-'  + toString( date.getHours(),     2 )

    ;

​

    return dateTimeNow;

}

​

console.log(getDateInFormat_yyyy_mm_dd()); // 2021-05-13

// output format: yyyy-mm-dd

function getDateInISO_8601() {

    let date = new Date();

    let year = '' + date.getFullYear();

    let month = '' + (date.getMonth() + 1);

    let day = '' + date.getDate();

​

    if (month.length < 2) {

        month = '0' + month;

    }

    if (day.length < 2) {

        day = '0' + day;

    }

    return year + '-' + month + '-' + day;

}

​

console.log(getDateInISO_8601()); // 2021-05-13

// output format: yyyy-mm-dd

//

function getIso8601Date(date) {

    if (date == null) {

        date = new Date();

    }

    var year = String(date.getFullYear());

    var month = String(date.getMonth() + 1);

    var day = String(date.getDate());

    if (month.length < 2) {

        month = '0' + month;

    }

    if (day.length < 2) {

        day = '0' + day;

    }

    return year + '-' + month + '-' + day;

}

​

// Usage example:

​

var now = new Date(2021, 05, 13); // 2021-05-13 - e.g. recived from server

​

console.log(getIso8601Date(now)); // 2021-05-13

console.log(getIso8601Date());    // 2021-05-13