All you need to know about Date in JavaScript
- Introduction
- Creating a Date Object
- Retrieving Date Components
- Setting Date Components
- Formatting Dates
- Parsing Dates
- Time Zones
- Calculating Time Intervals
- Dates in Libraries
- Handling Leap Years
- Time Zone Conversions
- Relative Dates
- Internationalization
- The issue of clock skew
- Best Practices
- Conclusion
Introduction
Date and time are fundamental concepts in software development. They are used in many applications, such as scheduling tasks, displaying events, and calculating time intervals. JavaScript provides a built-in object called Date that allows you to work with dates and times in your code. In this article, we'll cover everything you need to know about Date in JavaScript, including how to create and manipulate dates, format and parse dates, work with time zones, and calculate time intervals. We'll also discuss best practices for working with dates in JavaScript and common mistakes to avoid. By the end of this article, you'll have a solid understanding of how to work with dates in JavaScript and be able to use this knowledge to build more powerful and effective applications.
Creating a Date Object
In JavaScript, you can create a new Date object using the new Date() constructor. The Date object can accept various arguments to specify the date and time.
Creating a Date Object with Current Date and Time
To create a Date object with the current date and time, simply call the new Date() constructor with no arguments:
const today = new Date();
console.log(today);This will create a new Date object representing the current date and time.
Creating a Date Object with a Specific Date and Time
To create a Date object with a specific date and time, you can pass various arguments to the Date constructor. Here are some examples:
// Create a date object with a specific date and time
const date1 = new Date("2023-03-10T10:00:00");
console.log(date1);
// Create a date object with specific year, month, day, hour, minute, and second
const date2 = new Date(2023, 2, 10, 10, 0, 0);
console.log(date2);In the first example, we pass a string representing a specific date and time in ISO 8601 format. In the second example, we pass individual components of the date and time as arguments to the Date constructor.
Note that the month argument in the second example is zero-indexed, meaning that January is represented by 0, February by 1, and so on. Therefore, to create a date object representing March, we pass 2 as the month argument.
In addition to these examples, the Date constructor accepts many other argument formats to create a date object. Refer to the MDN documentation for more information.
Creating a Date object is the first step in working with dates in JavaScript. With a Date object, you can perform various operations, such as retrieving and setting individual date and time components, formatting dates for display, and calculating time intervals.
Retrieving Date Components
Once you have a Date object, you can retrieve individual components of the date and time using various methods.
Retrieving the Year
To retrieve the year of a Date object, use the getFullYear() method:
const date = new Date();
const year = date.getFullYear();
console.log(year);This will log the current year to the console.
Retrieving the Month
To retrieve the month of a Date object, use the getMonth() method:
const date = new Date();
const month = date.getMonth();
console.log(month);This will log the current month to the console. Note that the month is zero-indexed, meaning that January is represented by 0, February by 1, and so on.
Retrieving the Day of the Month
To retrieve the day of the month of a Date object, use the getDate() method:
const date = new Date();
const day = date.getDate();
console.log(day);This will log the current day of the month to the console.
Retrieving the Day of the Week
To retrieve the day of the week of a Date object, use the getDay() method:
const date = new Date();
const dayOfWeek = date.getDay();
console.log(dayOfWeek);This will log the current day of the week to the console as a number, where Sunday is represented by 0, Monday by 1, and so on.
Retrieving the Hour
To retrieve the hour of a Date object, use the getHours() method:
const date = new Date();
const hour = date.getHours();
console.log(hour);This will log the current hour to the console.
Retrieving the Minute
To retrieve the minute of a Date object, use the getMinutes() method:
const date = new Date();
const minute = date.getMinutes();
console.log(minute);This will log the current minute to the console.
Retrieving the Second
To retrieve the second of a Date object, use the getSeconds() method:
const date = new Date();
const second = date.getSeconds();
console.log(second);This will log the current second to the console.
Retrieving the Millisecond
To retrieve the millisecond of a Date object, use the getMilliseconds() method:
const date = new Date();
const millisecond = date.getMilliseconds();
console.log(millisecond);This will log the current millisecond to the console.
Retrieving individual date and time components of a Date object is useful when you need to perform calculations or display the date and time in a specific format. With these methods, you can extract the specific component you need and use it in your code.
Setting Date Components
In addition to retrieving individual date and time components of a Date object, you can also set them using various methods.
Setting the Year
To set the year of a Date object, use the setFullYear() method:
const date = new Date();
date.setFullYear(2024);
console.log(date);This will set the year of the Date object to 2024.
Setting the Month
To set the month of a Date object, use the setMonth() method:
const date = new Date();
date.setMonth(5);
console.log(date);This will set the month of the Date object to June (month index 5).
Setting the Day of the Month
To set the day of the month of a Date object, use the setDate() method:
const date = new Date();
date.setDate(15);
console.log(date);This will set the day of the month of the Date object to the 15th.
Setting the Hour
To set the hour of a Date object, use the setHours() method:
const date = new Date();
date.setHours(13);
console.log(date);This will set the hour of the Date object to 1 PM.
Setting the Minute
To set the minute of a Date object, use the setMinutes() method:
const date = new Date();
date.setMinutes(30);
console.log(date);This will set the minute of the Date object to 30.
Setting the Second
To set the second of a Date object, use the setSeconds() method:
const date = new Date();
date.setSeconds(45);
console.log(date);This will set the second of the Date object to 45.
Setting the Millisecond
To set the millisecond of a Date object, use the setMilliseconds() method:
const date = new Date();
date.setMilliseconds(500);
console.log(date);This will set the millisecond of the Date object to 500.
Setting individual date and time components of a Date object is useful when you need to modify a specific part of the date or time. With these methods, you can update the Date object to represent the new date and time you want.
Formatting Dates
In addition to retrieving and setting individual date and time components of a Date object, you can also format the date for display using various methods.
toLocaleDateString()
The toLocaleDateString() method returns a string representing the date portion of a Date object in a format appropriate for the current locale:
const date = new Date();
const dateString = date.toLocaleDateString();
console.log(dateString);This will log the current date in a format appropriate for the current locale, such as 3/10/2023 in the United States.
toLocaleTimeString()
The toLocaleTimeString() method returns a string representing the time portion of a Date object in a format appropriate for the current locale:
const date = new Date();
const timeString = date.toLocaleTimeString();
console.log(timeString);This will log the current time in a format appropriate for the current locale, such as 10:30:00 AM in the United States.
toLocaleString()
The toLocaleString() method returns a string representing the date and time portions of a Date object in a format appropriate for the current locale:
const date = new Date();
const dateTimeString = date.toLocaleString();
console.log(dateTimeString);This will log the current date and time in a format appropriate for the current locale, such as 3/10/2023, 10:30:00 AM in the United States.
Formatting dates for display is useful when you need to present dates to users in a way that is readable and understandable. With these methods, you can format dates in a variety of ways to meet the needs of your application and its users.
Parsing Dates
In addition to creating new Date objects and formatting dates for display, you may also need to parse dates that are entered by users or retrieved from an external source.
Date.parse()
The Date.parse() method can be used to parse a string representing a date and time into a Date object:
const dateString = "2023-03-10T10:30:00.000Z";
const date = new Date(Date.parse(dateString));
console.log(date);This will parse the ISO 8601 date string "2023-03-10T10:30:00.000Z" and create a new Date object representing that date and time.
Note that the string passed to Date.parse() must be in a format recognized by the JavaScript engine. The ISO 8601 format is widely supported, but other formats may not be recognized.
Date.UTC()
The Date.UTC() method can be used to create a new Date object representing a specified date and time in UTC (Coordinated Universal Time):
const date = new Date(Date.UTC(2023, 2, 10, 10, 30, 0));
console.log(date);This will create a new Date object representing March 10, 2023 at 10:30:00 UTC.
new Date(year, month[, day[, hour[, minute[, second[, millisecond]]]]])
The Date constructor can also be used to create a new Date object with a specified date and time:
const date = new Date(2023, 2, 10, 10, 30, 0);
console.log(date);This will create a new Date object representing March 10, 2023 at 10:30:00 local time.
When using the Date constructor, note that the month argument is zero-indexed, meaning that January is represented by 0, February by 1, and so on.
Parsing dates in JavaScript can be challenging due to the variety of date formats used around the world. However, with the methods provided by the Date object, you can parse dates in a variety of formats and create new Date objects to represent them.
Working with Time Zones
Working with time zones is an important aspect of working with dates in JavaScript, especially when dealing with dates and times that are used across different locations.
getTimezoneOffset()
The getTimezoneOffset() method returns the difference between the local time zone and UTC (Coordinated Universal Time) in minutes:
const date = new Date();
const offset = date.getTimezoneOffset();
console.log(offset);This will log the difference between the local time zone and UTC in minutes to the console.
Note that the getTimezoneOffset() method returns a negative value if the local time zone is ahead of UTC (such as in the United States) and a positive value if the local time zone is behind UTC (such as in India).
Setting Time Zones
JavaScript provides several methods for setting the time zone of a Date object, including toLocaleString(), toLocaleDateString(), and toLocaleTimeString():
const date = new Date();
const options = { timeZone: "America/Los_Angeles" };
console.log(date.toLocaleString("en-US", options));
console.log(date.toLocaleDateString("en-US", options));
console.log(date.toLocaleTimeString("en-US", options));This will log the current date and time in the Pacific Time Zone to the console.
When setting the time zone of a Date object, you can use the IANA Time Zone database to specify the time zone. The database includes time zone names, abbreviations, and UTC offsets for locations around the world.
Working with time zones in JavaScript can be complex, but by understanding how to set and retrieve time zone information, you can ensure that your applications accurately handle date and time information across different locations.
Calculating Time Intervals
When working with dates and times in JavaScript, you may need to calculate the amount of time that has passed between two dates, or add or subtract a certain amount of time from a given date. Here are some methods you can use to calculate time intervals:
getTime()
The getTime() method returns the number of milliseconds since January 1, 1970, 00:00:00 UTC. To calculate the number of milliseconds between two dates, you can subtract the earlier date from the later date and retrieve the result using the getTime() method:
const startDate = new Date("2022-01-01T00:00:00.000Z");
const endDate = new Date("2022-02-01T00:00:00.000Z");
const timeDiff = endDate.getTime() - startDate.getTime();
console.log(timeDiff); // output: 2678400000 (milliseconds)This will calculate the number of milliseconds between January 1, 2022 and February 1, 2022.
setTime()
The setTime() method sets the time of a Date object to a specified number of milliseconds since January 1, 1970, 00:00:00 UTC. To add or subtract a certain amount of time from a date, you can retrieve the current time using getTime(), add or subtract the desired number of milliseconds, and set the time of the Date object using setTime():
const startDate = new Date("2022-01-01T00:00:00.000Z");
const timeDiff = 2678400000; // 31 days in milliseconds
const endDate = new Date(startDate.getTime() + timeDiff);
console.log(endDate.toISOString()); // output: 2022-02-01T00:00:00.000ZThis will add 31 days to January 1, 2022 to calculate February 1, 2022.
setFullYear(), setMonth(), setDate(), setHours(), setMinutes(), setSeconds(), setMilliseconds()
The setFullYear(), setMonth(), setDate(), setHours(), setMinutes(), setSeconds(), and setMilliseconds() methods can be used to set the individual components of a Date object (year, month, day, hour, minute, second, and millisecond) to a specified value. For example, to set the month of a Date object to February, you can use the setMonth() method:
const date = new Date("2022-01-15T00:00:00.000Z");
date.setMonth(1); // February (0-indexed)
console.log(date.toISOString()); // output: 2022-02-15T00:00:00.000ZThis will set the month of the Date object to February, while leaving the other components (year, day, hour, minute, second, and millisecond) unchanged.
By understanding and using these methods for calculating time intervals, you can perform complex date and time calculations in JavaScript with ease.
Working with Dates in Libraries
JavaScript has several libraries that can help you work with dates more easily and accurately. Here are a few popular libraries:
Moment.js
Moment.js is a popular library for working with dates and times in JavaScript. It provides a simple and consistent API for parsing, formatting, and manipulating dates and times.
Here’s an example of how to use Moment.js:
const date = moment();
const dateString = date.format("YYYY-MM-DD HH:mm:ss");
console.log(dateString);This will log the current date and time in the format YYYY-MM-DD HH:mm:ss.
Luxon
Luxon is a modern JavaScript library for working with dates and times. It provides a powerful and intuitive API for parsing, formatting, and manipulating dates and times.
Here’s an example of how to use Luxon:
const date = DateTime.now();
const dateString = date.toFormat("yyyy-MM-dd HH:mm:ss");
console.log(dateString);This will log the current date and time in the format yyyy-MM-dd HH:mm:ss.
Day.js
Day.js is a minimalist JavaScript library for working with dates and times. It provides a simple and easy-to-use API for parsing, formatting, and manipulating dates and times.
Here’s an example of how to use Day.js:
const date = dayjs();
const dateString = date.format("YYYY-MM-DD HH:mm:ss");
console.log(dateString);This will log the current date and time in the format YYYY-MM-DD HH:mm:ss.
Using a library like Moment.js, Luxon, or Day.js can help you work with dates and times more easily and with fewer bugs. These libraries provide powerful and intuitive APIs that can simplify complex date and time operations.
Handling Leap Years
Leap years are years that are evenly divisible by 4, except for years that are divisible by 100 but not by 400. For example, the year 2000 was a leap year because it is divisible by 4 and by 400, but the year 1900 was not a leap year because it is divisible by 100 but not by 400.
When working with dates in JavaScript, it’s important to account for leap years to ensure that calculations involving dates are accurate. Here are a few tips for handling leap years:
Checking if a year is a leap year
To check if a year is a leap year in JavaScript, you can use the following formula:
function isLeapYear(year) {
return (year % 4 === 0 && year % 100 !== 0) || (year % 400 === 0);
}This function returns true if the year is a leap year, and false otherwise.
Adjusting for leap year
When working with dates that may be affected by leap years, such as February 29th, it’s important to adjust calculations to account for the extra day in leap years.
For example, to calculate the number of days between two dates in JavaScript, you can subtract the earlier date from the later date and divide the result by the number of milliseconds in a day:
const oneDay = 24 * 60 * 60 * 1000; // Number of milliseconds in a day
const startDate = new Date(2020, 1, 1); // February 1, 2020
const endDate = new Date(2021, 1, 1); // February 1, 2021
const daysBetween = Math.round(Math.abs((endDate - startDate) / oneDay));
console.log(daysBetween);This will calculate the number of days between February 1, 2020 and February 1, 2021. However, since 2020 is a leap year, this calculation will not account for the extra day in February. To adjust for this, you can check if the year is a leap year and add one day to the calculation if the date range includes February 29th:
const oneDay = 24 * 60 * 60 * 1000; // Number of milliseconds in a day
const startDate = new Date(2020, 1, 1); // February 1, 2020
const endDate = new Date(2021, 1, 1); // February 1, 2021
const daysBetween = Math.round(Math.abs((endDate - startDate) / oneDay));
const isLeapYear = isLeapYear(startDate.getFullYear());
if (isLeapYear && startDate.getMonth() <= 1 && endDate.getMonth() >= 2) {
daysBetween++;
}
console.log(daysBetween);This will adjust the calculation to add one day if the date range includes February 29th in a leap year.
By accounting for leap years when working with dates in JavaScript, you can ensure that your calculations and date manipulations are accurate and reliable.
Time Zone Conversions
Converting dates and times between different time zones can be challenging, especially when dealing with daylight saving time transitions and time zone abbreviations. Here are some tips for working with time zones in JavaScript:
Use UTC for server-side operations
When working with dates on the server side, it’s best to use UTC to ensure that date calculations are consistent across different time zones. You can use the toISOString() method to convert a Date object to a string in ISO format, which represents the date and time in UTC:
const date = new Date();
const utcString = date.toISOString();
console.log(utcString);This will log the current date and time in UTC in the format YYYY-MM-DDTHH:mm:ss.sssZ.
Use Intl.DateTimeFormat() for user-facing output
When displaying dates to users, it’s best to format the dates according to the user’s locale and time zone. You can use the Intl.DateTimeFormat() method to format a Date object according to the user's locale:
const date = new Date();
const options = { timeZone: 'America/Los_Angeles' };
const formatter = new Intl.DateTimeFormat('en-US', options);
const dateString = formatter.format(date);
console.log(dateString);This will format the Date object according to the en-US locale and the America/Los_Angeles time zone.
Use a library for complex time zone operations
For complex time zone operations, such as converting dates between different time zones or dealing with daylight saving time transitions, it’s best to use a library like Moment.js, Luxon, or Day.js. These libraries provide a powerful and intuitive API for working with time zones and can help simplify complex time zone operations.
Beware of daylight saving time transitions
Daylight saving time transitions can be especially tricky when working with time zones. During a daylight saving time transition, the clock either moves forward or backward by one hour, which can affect the date and time calculations. To handle daylight saving time transitions, it’s best to use a library like Moment.js, Luxon, or Day.js, which provide built-in support for daylight saving time transitions.
By using the tips and tools above, you can effectively handle time zone conversions when working with dates in JavaScript, and ensure that your applications provide a consistent and accurate user experience.
Relative Dates
When working with dates in JavaScript, you may need to calculate relative dates, such as “today”, “yesterday”, or “last week”. Here are some tips for working with relative dates:
Use a library for complex relative date calculations
For complex relative date calculations, such as calculating the number of weeks since a given date or the last occurrence of a weekday, it’s best to use a library like Moment.js, Luxon, or Day.js. These libraries provide a powerful and intuitive API for working with relative dates and can help simplify complex calculations.
Use toLocaleDateString() for simple relative dates
For simple relative dates, such as “today”, “yesterday”, or “tomorrow”, you can use the toLocaleDateString() method to format a Date object as a relative date string:
const today = new Date();
const yesterday = new Date(today);
yesterday.setDate(yesterday.getDate() - 1);const todayString = today.toLocaleDateString('en-US', { weekday: 'long', year: 'numeric', month: 'long', day: 'numeric' });
const yesterdayString = yesterday.toLocaleDateString('en-US', { weekday: 'long' });
console.log(todayString); // output: Wednesday, March 10, 2023
console.log(yesterdayString); // output: TuesdayThis will format the Date object as a relative date string according to the user's locale.
Use Date.now() for current date and time
To get the current date and time as a Date object, you can use the Date.now() method, which returns the number of milliseconds since January 1, 1970, 00:00:00 UTC:
const now = new Date(Date.now());
console.log(now.toLocaleString());This will log the current date and time in the user’s local time zone.
Use setHours(), setMinutes(), setSeconds(), setMilliseconds() for time components
When working with relative dates, it’s important to set the time components of a Date object to 0 to ensure that date comparisons are accurate. You can use the setHours(), setMinutes(), setSeconds(), and setMilliseconds() methods to set the time components of a Date object to 0:
const date = new Date();
date.setHours(0, 0, 0, 0); // Set time components to 0
console.log(date.toLocaleString());This will set the time components of the Date object to 0, leaving only the date components.
By using these tips and tools, you can effectively work with relative dates when working with dates in JavaScript and provide a user-friendly date and time experience for your users.
Internationalization
When working with dates in JavaScript, it’s important to format dates according to the user’s locale and language. Here are some tips for internationalizing dates in JavaScript:
Use toLocaleString() for formatting
The toLocaleString() method can be used to format a Date object according to the user's locale:
const date = new Date();
const options = { weekday: 'long', year: 'numeric', month: 'long', day: 'numeric' };
const localeString = date.toLocaleString('en-US', options);
console.log(localeString);This will format the Date object according to the en-US locale.
Use Intl.DateTimeFormat() for more customization
For more control over the formatting of dates, you can use the Intl.DateTimeFormat() constructor to create a formatter object. This allows you to specify the locale, time zone, and formatting options:
const date = new Date();
const options = { timeZone: 'America/Los_Angeles', year: 'numeric', month: 'long', day: 'numeric' };
const formatter = new Intl.DateTimeFormat('en-US', options);
const dateString = formatter.format(date);
console.log(dateString);This will format the Date object according to the en-US locale, with the year, month, and day in the format Month Day, Year.
Use a library for complex internationalization
For complex internationalization, such as formatting dates with custom formats or handling different calendar systems, it’s best to use a library like Moment.js, Luxon, or Day.js. These libraries provide a powerful and intuitive API for internationalizing dates and can help simplify complex internationalization.
Use navigator.language for detecting the user's language
To detect the user’s language, you can use the navigator.language property, which returns a string representing the user's preferred language:
const userLanguage = navigator.language;
console.log(userLanguage);This will log the user’s language, such as en-US or fr-FR.
By internationalizing dates in your JavaScript applications, you can provide a more user-friendly experience for users in different parts of the world and ensure that your applications are accessible to a wider audience.
The issue of clock skew
The issue of clock skew refers to the fact that clocks on different devices or servers may not be perfectly synchronized, which can cause issues when comparing or calculating dates and times.
For example, let’s say you have a web application that relies on accurate date and time calculations, such as an online booking system that needs to ensure that reservations are made for the correct date and time. If the clocks on the user’s device and the server where the application is running are not perfectly synchronized, it can cause issues when comparing or calculating dates and times.
Consider the following code:
const now = new Date();
const futureDate = new Date(now.getTime() + (24 * 60 * 60 * 1000)); // Add 1 dayif (futureDate > now) {
console.log('The future date is after the current date.');
} else {
console.log('The future date is before or the same as the current date.');
}This code creates a Date object representing the current date and time, adds 1 day to the current date, and then compares the future date to the current date. If the future date is after the current date, it logs a message to the console.
However, if the clocks on the user’s device and the server where the application is running are not perfectly synchronized, it can cause issues when comparing the two dates. For example, if the user’s device clock is ahead of the server clock by a few seconds, the future date calculated on the user’s device may be slightly ahead of the future date calculated on the server, causing the comparison to fail.
To avoid issues with clock skew, it’s important to use reliable time synchronization services or protocols, such as NTP (Network Time Protocol). It’s also important to use libraries like Moment.js, Luxon, or Day.js, which provide robust and reliable date and time calculations that are not affected by clock skew.
By being aware of the issue of clock skew and taking appropriate steps to address it, developers can ensure that their applications provide accurate and reliable date and time functionality.
Best Practices
Working with dates in JavaScript can be tricky, especially when dealing with time zones, different date formats, and leap years. Here are some best practices to keep in mind when working with dates in JavaScript:
Always use UTC for server-side operations
When working with dates on the server side, it’s best to use UTC to ensure that date calculations are consistent across different time zones. You can use the toISOString() method to convert a Date object to a string in ISO format, which represents the date and time in UTC:
const date = new Date();
const utcString = date.toISOString();
console.log(utcString);This will log the current date and time in UTC in the format YYYY-MM-DDTHH:mm:ss.sssZ.
Use a library for complex date and time operations
For complex date and time operations, such as working with time zones or calculating relative dates, it’s best to use a library like Moment.js, Luxon, or Day.js. These libraries provide a powerful and intuitive API for working with dates and times, and can help simplify complex date operations.
Validate user input
When accepting date input from users, it’s important to validate the input to ensure that it is in the correct format and represents a valid date. You can use the Date.parse() method to parse a date string, which returns the number of milliseconds since January 1, 1970, 00:00:00 UTC if the string represents a valid date, or NaN otherwise:
const dateString = "2022-01-01";
const timestamp = Date.parse(dateString);
if (isNaN(timestamp)) {
console.log("Invalid date string");
} else {
const date = new Date(timestamp);
console.log(date.toISOString());
}This will log the date string in ISO format if it represents a valid date, or an error message otherwise.
Date and time input from users
Use a date picker or other input control that can validate and format user input values, and consider using a library like Moment.js, Luxon, or Day.js that has built-in support for handling date and time input from user
Test with different time zones and locales
When testing your application, it’s important to test with different time zones and locales to ensure that your application works correctly for users in different parts of the world. You can use the getTimezoneOffset() method to retrieve the difference in minutes between the user's local time and UTC:
const date = new Date();
const offsetMinutes = date.getTimezoneOffset();
console.log(offsetMinutes);This will log the difference in minutes between the user’s local time and UTC. You can also use the toLocaleString() method to format a Date object according to the user's locale:
const date = new Date();
const options = { weekday: 'long', year: 'numeric', month: 'long', day: 'numeric' };
const localeString = date.toLocaleString('en-US', options);
console.log(localeString);This will format the Date object according to the en-US locale.
By following these best practices, you can ensure that your JavaScript applications accurately handle date and time information, and provide a consistent user experience for users around the world.
Conclusion
The Date object is a powerful tool for working with dates and times in JavaScript. With the Date object, you can create new dates, retrieve and set individual components of dates, format dates for display, and parse dates entered by users or retrieved from external sources.
Working with dates in JavaScript can be challenging, especially when dealing with time zones and different date formats. However, by understanding the methods provided by the Date object and using a library like Moment.js, Luxon, or Day.js, you can simplify complex date and time operations and ensure that your applications accurately handle date and time information across different locations.
By mastering the Date object in JavaScript, you can become an expert in handling dates and times in your JavaScript applications and build better user experiences for your users.
Thanks to ChatGPT.