The complete resource for understanding, converting, and implementing date formats across all systems, programming languages, and regional standards.
Convert between any date format instantly. Supports all major standards and regional variations.
Understanding the most widely used date format notations worldwide.
Day/Month/Year format used in most of Europe, Latin America, Asia, and Africa. Logical progression from smallest to largest unit.
Month/Day/Year format primarily used in the United States. Reflects how dates are spoken in American English.
ISO 8601 international standard. Sortable and unambiguous. Preferred for databases and technical applications.
Seconds elapsed since January 1, 1970 UTC. Universal time representation in computing systems.
Internet Message Format standard. Includes day name and timezone. Used in email headers and HTTP.
Milliseconds since Unix epoch. JavaScript and modern API standard for precise timestamps.
How different countries and cultures represent dates.
Examples: 31/12/2024, 31.12.2024
Example: 12/31/2024
Example: 2024年12月31日
Dual calendar systems
Code snippets for handling dates in popular programming languages.
// JavaScript Date Formatting
const date = new Date('2024-12-31');
// Various formats
date.toLocaleDateString('en-GB'); // 31/12/2024
date.toLocaleDateString('en-US'); // 12/31/2024
date.toISOString(); // 2024-12-31T00:00:00.000Z
date.getTime(); // 1735689600000 (epoch ms)
// Custom formatting
const formatDate = (date) => {
const dd = String(date.getDate()).padStart(2, '0');
const mm = String(date.getMonth() + 1).padStart(2, '0');
const yyyy = date.getFullYear();
return `${dd}/${mm}/${yyyy}`;
};# Python Date Formatting
from datetime import datetime
import time
date = datetime(2024, 12, 31)
# Various formats
date.strftime('%d/%m/%Y') # 31/12/2024
date.strftime('%m/%d/%Y') # 12/31/2024
date.strftime('%Y-%m-%d') # 2024-12-31
int(date.timestamp()) # 1735689600 (Unix timestamp)
# ISO format
date.isoformat() # 2024-12-31T00:00:00
# Parse from string
parsed = datetime.strptime('31/12/2024', '%d/%m/%Y')// Java Date Formatting
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
LocalDate date = LocalDate.of(2024, 12, 31);
// Various formats
DateTimeFormatter eu = DateTimeFormatter.ofPattern("dd/MM/yyyy");
DateTimeFormatter us = DateTimeFormatter.ofPattern("MM/dd/yyyy");
DateTimeFormatter iso = DateTimeFormatter.ISO_DATE;
date.format(eu); // 31/12/2024
date.format(us); // 12/31/2024
date.format(iso); // 2024-12-31
// Parse from string
LocalDate parsed = LocalDate.parse("31/12/2024", eu);// C# Date Formatting
DateTime date = new DateTime(2024, 12, 31);
// Various formats
date.ToString("dd/MM/yyyy"); // 31/12/2024
date.ToString("MM/dd/yyyy"); // 12/31/2024
date.ToString("yyyy-MM-dd"); // 2024-12-31
date.ToString("o"); // 2024-12-31T00:00:00.0000000
// Unix timestamp
DateTimeOffset dto = new DateTimeOffset(date);
dto.ToUnixTimeSeconds(); // 1735689600
// Parse from string
DateTime parsed = DateTime.ParseExact("31/12/2024",
"dd/MM/yyyy",
CultureInfo.InvariantCulture);// PHP Date Formatting
$date = new DateTime('2024-12-31');
// Various formats
$date->format('d/m/Y'); // 31/12/2024
$date->format('m/d/Y'); // 12/31/2024
$date->format('Y-m-d'); // 2024-12-31
$date->format('U'); // 1735689600 (Unix timestamp)
// ISO 8601
$date->format('c'); // 2024-12-31T00:00:00+00:00
// Parse from string
$parsed = DateTime::createFromFormat('d/m/Y', '31/12/2024');
// Using strtotime
$timestamp = strtotime('31 December 2024');# Ruby Date Formatting
require 'date'
date = Date.new(2024, 12, 31)
# Various formats
date.strftime('%d/%m/%Y') # 31/12/2024
date.strftime('%m/%d/%Y') # 12/31/2024
date.strftime('%Y-%m-%d') # 2024-12-31
date.to_time.to_i # 1735689600 (Unix timestamp)
# ISO 8601
date.iso8601 # 2024-12-31
# Parse from string
parsed = Date.strptime('31/12/2024', '%d/%m/%Y')
# Using Date.parse
parsed2 = Date.parse('31 December 2024')Official standards that govern date and time representations globally.
The international standard for date and time representation. Defines unambiguous date formats like YYYY-MM-DD and includes provisions for week dates, ordinal dates, and time zones.
2024-12-31
2024-W52-2
2024-365
2024-12-31T23:59:59Z
Profile of ISO 8601 for use in Internet protocols. Specifies date/time format for use in Internet protocols and standards like JSON, XML, and APIs.
2024-12-31T23:59:59Z
2024-12-31T23:59:59.999Z
2024-12-31T23:59:59+00:00
Number of seconds since January 1, 1970 00:00:00 UTC. Standard time representation in Unix and Unix-like systems. Reaches 2^31 limit in 2038.
1735689599
0 = 1970-01-01T00:00:00Z
2147483647 = 2038-01-19
Date and time formats used in HTML, XML Schema, and web technologies. Based on ISO 8601 with specific profiles for web use.
<time datetime="2024-12-31">
xs:dateTime
xs:date
Essential resources for working with date formats.
Common questions about date formats and standards.
ISO 8601 (YYYY-MM-DD) is the international standard and is unambiguous, sortable, and recognized worldwide. It's the recommended format for databases, APIs, and international communication.
The US format reflects how Americans typically speak dates (e.g., "December 31st" becomes 12/31). This convention dates back to colonial times and has persisted despite international standardization efforts.
The Year 2038 problem occurs when 32-bit Unix timestamps overflow on January 19, 2038. Systems using 32-bit time representations will need updates to 64-bit timestamps.
Always store dates in UTC and convert to local time for display. Use ISO 8601 with timezone offset (e.g., 2024-12-31T23:59:59+02:00) or specify UTC with 'Z' suffix.
They're essentially the same - both count from January 1, 1970 00:00:00 UTC. Unix timestamp typically uses seconds, while JavaScript and other systems may use milliseconds.
YYYY-MM-DD or YYYYMMDD is best for file names as it sorts chronologically and avoids confusion. Avoid slashes (/) as they're directory separators in file systems.