The Date object in JavaScript is used to work with dates and times. It provides methods to create, manipulate, and format date and time values.
Creating Dates
You can create a Date object in multiple ways:
- Current Date and Time:
const now = new Date(); console.log(now); // Current date and time
- Specific Date:
const specificDate = new Date(2024, 10, 21); // Year, Month (0-based), Day console.log(specificDate); // Thu Nov 21 2024
- From a String:
const fromString = new Date("2024-11-21T10:00:00"); console.log(fromString); // Thu Nov 21 2024 10:00:00 GMT
- From Timestamps (milliseconds since Unix epoch):
const fromTimestamp = new Date(1732231200000); console.log(fromTimestamp); // Thu Nov 21 2024 10:00:00 GMT
Common Methods
Getting Date and Time
|
Description |
Example | |||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
getFullYear() | Returns the year | date.getFullYear() -> 2024 | |||||||||||||||||||||||||||
getMonth() | Returns the month (0-11) | date.getMonth() -> 10 (November) | |||||||||||||||||||||||||||
getDate() | Returns the day of the month (1-31) | date.getDate() -> 21 | |||||||||||||||||||||||||||
getDay() | Returns the weekday (0-6, Sun=0) | date.getDay() -> 4 (Thursday) | |||||||||||||||||||||||||||
getHours() | Returns the hour (0-23) | date.getHours() -> 10 | |||||||||||||||||||||||||||
getMinutes() | Returns the minutes (0-59) | date.getMinutes() -> 0 | |||||||||||||||||||||||||||
getSeconds() | Returns the seconds (0-59) | date.getSeconds() -> 0 | |||||||||||||||||||||||||||
getTime() | Returns timestamp in milliseconds | date.getTime() -> 1732231200000 |
Method | Description | Example |
---|---|---|
setFullYear(year) | Sets the year | date.setFullYear(2025) |
setMonth(month) | Sets the month (0-11) | date.setMonth(0) -> January |
setDate(day) | Sets the day of the month | date.setDate(1) -> First day of the month |
setHours(hour) | Sets the hour (0-23) | date.setHours(12) |
setMinutes(minutes) | Sets the minutes (0-59) | date.setMinutes(30) |
setSeconds(seconds) | Sets the seconds (0-59) | date.setSeconds(45) |
Method | Description | Example |
---|---|---|
setFullYear(year) | Sets the year | date.setFullYear(2025) |
setMonth(month) | Sets the month (0-11) | date.setMonth(0) -> January |
setDate(day) | Sets the day of the month | date.setDate(1) -> First day of the month |
setHours(hour) | Sets the hour (0-23) | date.setHours(12) |
setMinutes(minutes) | Sets the minutes (0-59) | date.setMinutes(30) |
setSeconds(seconds) | Sets the seconds (0-59) | date.setSeconds(45) |
Formatting Dates
|
Description |
Example | |||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
toDateString() | Returns date as a human-readable string | date.toDateString() -> "Thu Nov 21 2024" | |||||||||||||||
toISOString() | Returns date in ISO format | date.toISOString() -> "2024-11-21T10:00:00.000Z" | |||||||||||||||
toLocaleDateString() | Returns date in localized format | date.toLocaleDateString() -> "11/21/2024" | |||||||||||||||
toLocaleTimeString() | Returns time in localized format | date.toLocaleTimeString() -> "10:00:00 AM" |
- Common Use Cases
const now = new Date(); console.log(now); // Current date and time
- Calculate Days Between Two Dates
- :
const specificDate = new Date(2024, 10, 21); // Year, Month (0-based), Day console.log(specificDate); // Thu Nov 21 2024
- Countdown Timer
- :
const fromString = new Date("2024-11-21T10:00:00"); console.log(fromString); // Thu Nov 21 2024 10:00:00 GMT
- Format Current Date
- :
const fromTimestamp = new Date(1732231200000); console.log(fromTimestamp); // Thu Nov 21 2024 10:00:00 GMT
- Find the Day of the Week
- :
const startDate = new Date("2024-11-01"); const endDate = new Date("2024-11-21"); const diffInTime = endDate - startDate; // Difference in milliseconds const diffInDays = diffInTime / (1000 * 60 * 60 * 24); // Convert to days console.log(diffInDays); // 20
- Check Leap Year
- :
const targetDate = new Date("2024-12-31T23:59:59"); setInterval(() => { const now = new Date(); const timeLeft = targetDate - now; // Milliseconds left const days = Math.floor(timeLeft / (1000 * 60 * 60 * 24)); const hours = Math.floor((timeLeft / (1000 * 60 * 60)) % 24); const minutes = Math.floor((timeLeft / (1000 * 60)) % 60); const seconds = Math.floor((timeLeft / 1000) % 60); console.log(`${days}d ${hours}h ${minutes}m ${seconds}s`); }, 1000);
Add/Subtract Days
:
- Pro Tips
const now = new Date(); const formatted = `${now.getFullYear()}-${now.getMonth() + 1}-${now.getDate()}`; console.log(formatted); // "2024-11-21"Use
- Date.now()
- to get the current timestamp directly without creating a Date object:
Be mindful of time zones
when working with dates across regions. Use libraries like Moment.js - or
Day.js for advanced handling.
0-indexed
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