Are Javascript date/time functions dependent on the client machine?

Question

I was wondering if Javascript date/time functions will always return correct, universal dates/times or whether, Javascript being a client-side language, they are dependent

Answer 1

Javascript's date() constructor will always get the time of local machine.

The best way to get the universal time are

1) get the time from your server by an ajax call. This method will always show your server time no matter where your user is.

2) Get the time from an third party server. Use a third party server to get time from any time zone / country of the world. Here I'm explaining this method by using plain javascript and axios. The service I'm using is worldtimeapi.org/

VANILLA JS

function getTime(url) {
    return new Promise((resolve, reject) => {
        const req = new XMLHttpRequest();
        req.open("GET", url);
        req.onload = () =>
            req.status === 200
                ? resolve(req.response)
                : reject(Error(req.statusText));
        req.onerror = (e) => reject(Error(`Network Error: ${e}`));
        req.send();
    });
}

Now Use this function to make the ajax call

let url = "http://worldtimeapi.org/api/timezone/Etc/GMT";

getTime(url)
    .then((response) => {
        let dateObj = JSON.parse(response);
        let dateTime = dateObj.datetime;
        console.log(dateObj);
        console.log(dateTime);
    })
    .catch((err) => {
        console.log(err);
    });

AXIOS

axios({
    url:"http://worldtimeapi.org/api/timezone/Etc/GMT",
    method: "get",
})
    .then((response) => {
        let dateObj = response.data;
        let dateTime = dateObj.datetime;
        console.log(dateObj);
        console.log(dateTime);
    })
    .catch((err) => {
        console.log(err);
    });

Hope that helps. Bear one thing in mind though, worldtimeapi.org/ is a third party service. If they choose to terminate their service, your code will break. Happy coding.