Date and Time Tools: Timestamps, Calculators, and Converters

Working with dates and times is a common programming task. Learn about timestamps, calculations, and conversions.

Unix Timestamps

What is a Unix Timestamp?

• Seconds since January 1, 1970 (UTC)
• Universal, timezone-independent
• Example: 1704067200 = January 1, 2024 00:00:00 UTC

JavaScript Timestamps

// Current timestamp (seconds)
const timestamp = Math.floor(Date.now() / 1000);

// From date to timestamp
const date = new Date('2024-01-01');
const ts = Math.floor(date.getTime() / 1000);

// From timestamp to date
const dateFromTs = new Date(timestamp * 1000);

Python Timestamps

import time
from datetime import datetime

# Current timestamp
timestamp = int(time.time())

# From datetime to timestamp
dt = datetime(2024, 1, 1)
ts = int(dt.timestamp())

# From timestamp to datetime
dt_from_ts = datetime.fromtimestamp(timestamp)

Date Calculations

Add/Subtract Days

function addDays(date, days) {
  const result = new Date(date);
  result.setDate(result.getDate() + days);
  return result;
}

// 30 days from now
const futureDate = addDays(new Date(), 30);

// 30 days ago
const pastDate = addDays(new Date(), -30);

Days Between Dates

function daysBetween(date1, date2) {
  const oneDay = 24 * 60 * 60 * 1000;
  return Math.round(Math.abs((date1 - date2) / oneDay));
}

Business Days

function addBusinessDays(date, days) {
  let result = new Date(date);
  let added = 0;

  while (added < days) {
    result.setDate(result.getDate() + 1);
    const dayOfWeek = result.getDay();
    if (dayOfWeek !== 0 && dayOfWeek !== 6) {
      added++;
    }
  }

  return result;
}

Time Conversions

Unit Conversions

From	To	Formula
Seconds	Minutes	/ 60
Minutes	Hours	/ 60
Hours	Days	/ 24
Days	Weeks	/ 7

Timezone Handling

// Get timezone offset
const offset = new Date().getTimezoneOffset(); // minutes

// Convert to specific timezone
function toTimezone(date, tz) {
  return new Date(date.toLocaleString('en-US', { timeZone: tz }));
}

const nyTime = toTimezone(new Date(), 'America/New_York');
const tokyoTime = toTimezone(new Date(), 'Asia/Tokyo');

Formatting Dates

JavaScript

const date = new Date();

// ISO format
date.toISOString(); // "2024-01-01T00:00:00.000Z"

// Locale format
date.toLocaleDateString('en-US'); // "1/1/2024"
date.toLocaleDateString('en-GB'); // "01/01/2024"

// Custom format with Intl
const formatter = new Intl.DateTimeFormat('en-US', {
  year: 'numeric',
  month: 'long',
  day: 'numeric'
});
formatter.format(date); // "January 1, 2024"

Try Our DateTime Tools

• Timestamp Converter
• Date Calculator
• Time Converter
• Random Time

Conclusion

Understanding date/time manipulation is crucial for scheduling, logging, and data processing.