Date & Time Calculator
Calculate differences between dates and times, add or subtract time periods, and plan your events with precision.
đź“… Calculate Date Difference
⏰ Calculate Time Difference
âž•âž– Add or Subtract Time
📆 Event Planner
Your calculation results will appear here.
Tickr
Never miss important dates again! Tickr calculates time differences, creates recurring events, syncs with your calendar, and sends smart reminders.
Download Tickrđź“ť How to Use
- Date Difference: Calculate days, weeks, months, and years between two dates
- Time Difference: Find the duration between two times, including overnight calculations
- Add/Subtract Time: Add or remove years, months, days, hours, minutes from any date
- Event Planner: Count down to important events and set reminders
Frequently Asked Questions
How do I calculate business days (excluding weekends)?
Use the "Date Difference" mode and check the "Show business days" option. This excludes Saturdays and Sundays from the count. For example, Monday to Friday of the same week = 5 business days, even though it's 4 calendar days apart (if you include the end date). Note that this calculator doesn't account for holidays—for precise business day calculations including holidays, you'd need to manually subtract holiday dates. Common workaround: calculate business days, then subtract the number of holidays that fall within your date range.
Should I include the end date in my calculation?
It depends on your context. If you're calculating "days between" (January 1 to January 5), excluding the end date gives you 4 days. If you're calculating "days from-to" including both boundary dates (like event duration), include the end date for 5 days. Real-world example: a 3-day weekend from Friday to Sunday. Friday to Sunday = 2 days apart, but it's a 3-day period. For project deadlines, typically exclude the end date (start Monday, due Friday = 4 working days). For vacation days or event duration, include the end date.
How do I calculate overnight time differences?
Use the "Time Difference" mode and check the "End time is next day" option. This is useful for night shifts, overnight flights, or sleep duration. For example, 11:00 PM to 7:00 AM with "next day" checked = 8 hours. Without that option, it would incorrectly calculate as if both times were the same day (showing -16 hours or an error). For calculations spanning multiple days, use "Add/Subtract Time" mode instead—enter your start datetime and add the hours/days to see the end datetime.
Why does adding 1 month to January 31st give me different results?
This is a calendar quirk—months have different lengths. January 31 + 1 month = February 28 (or 29 in leap years) because February doesn't have 31 days. The calculator uses the "end of month" behavior: it gives you the last day of the target month when the day doesn't exist. Similarly, January 31 + 1 month + 1 month = March 31 (not April 1). To add exactly 30 days regardless of month lengths, use the "days" field instead of "months"—this adds a fixed number of days. Months are calendar-based (variable length), days are duration-based (fixed length).
How do I account for time zones in my calculations?
This calculator uses your device's local time zone for all calculations. For cross-timezone calculations, manually convert times to the same timezone first. Example: Meeting at 3 PM EST and you're in PST—convert 3 PM EST to 12 PM PST, then use 12 PM in the calculator. For international date lines or complex timezone math, consider using a dedicated timezone converter first (like our Time Zone Converter tool), then use the results in this calculator. Future enhancement idea: built-in timezone support would handle this automatically, but for now, pre-conversion is most accurate.
Can I calculate my exact age in years, months, and days?
Yes! Use "Date Difference" mode with your birthdate as the start date and today's date as the end date. The result shows your age broken down by years, months, and days. Example result: "30 years, 4 months, and 12 days old." This is more precise than just saying you're "30 years old." For age in other units (hours, minutes, or seconds), use the breakdown provided—it's especially fun for milestone birthdays (10,000 days old, 1 million minutes, etc.). For a more detailed age calculator with additional features, check out our dedicated Age Calculator tool.
Common Use Cases
Project Management
Calculate project timelines, milestone dates, and deadlines. Use "Add/Subtract Time" to set deadlines (start date + project duration), or "Date Difference" to track progress (days remaining until deadline).
Travel Planning
Calculate trip duration, countdown to vacation, or flight durations. Remember to account for timezone changes when booking international flights—this calculator uses local time.
Personal Milestones
Track pregnancies (due dates), baby ages, relationship anniversaries, or sobriety milestones. Seeing exact time elapsed (in months and days) can be motivating for personal goals.
Financial Calculations
Calculate investment holding periods, loan terms, or billing cycles. Many financial calculations require exact day counts—use "Date Difference" with end date included for precise day counts.