Date Calculator

What your result means

The calculator shows the same gap between two dates in several ways. Pick the row that answers your question.

By default, the count leaves out the end date. Tick Include end date to count both the first and the last day, which adds one day to every row.

How the date difference is calculated

Total days = end date − start date, plus 1 if you include the end date.

For years, months and days, the calculator uses the same whole-month method as our age calculator:

• Whole months: step forward from the start date one month at a time, as far as you can without passing the end date. If a month is too short, use its last day, so 31 January plus 1 month is 28 February.
• Days: count the days left from that point to the end date.
• Years: whole months ÷ 12 gives years, and the remainder is months.

Weeks = total days ÷ 7, with the remainder shown as days. Working days and weekend days are counted over the same period: from the start date up to the day before the end date, or up to the end date itself if you include it. Leap days are counted automatically, because the calculator works with real calendar dates.

How to use the date calculator

1. Enter the start date. It is set to today when the page opens. Type the day, pick the month and type the year, or use the calendar button.
2. Enter the end date. It can be before or after the start date. If it is earlier, the calculator swaps the two dates and tells you.
3. Tick Include end date if both days should count, for example for leave or an event that runs from one date to another.
4. Read the results. They update as soon as both dates are complete.

Dates can go back to 1900 and up to 100 years ahead.

Worked example

On Sunday, 18 October 2026, Sneha checks how long she has until her exam on Monday, 15 February 2027.

1. Whole months: 18 October 2026 plus 3 months is 18 January 2027. One more month would be 18 February, which is past the exam, so 3 months stands.
2. Days: from 18 January to 15 February 2027 is 28 days.
3. Total days: 13 days left in October + 30 in November + 31 in December + 31 in January + 15 in February = 120 days.
4. Weeks: 120 ÷ 7 = 17 weeks and 1 day.
5. Working days: from 18 October 2026 to 14 February 2027 there are 85 weekdays and 35 weekend days.

The headline reads 3 months, 28 days, and the last row shows “120 days from today”. With Include end date ticked, the exam day is counted too: 121 days, 3 months and 29 days, 17 weeks and 2 days, and 86 working days.

Inclusive or exclusive: which count do you need?

This is the most common reason two people get different answers. Monday to Friday of the same week is 4 days if you count the gaps, but 5 days if you count both Monday and Friday.

• Leave and events: usually count both days. Leave from Monday 19 to Sunday 25 October 2026 is 7 days, so tick Include end date. It covers 5 working days.
• Countdowns and “days until”: leave the end date out. The “End date from today” row already does this.
• Rent, loan and interest days: lenders often count each day the money is out, which is usually the exclusive count. Check your agreement.
• Legal periods: under Section 9 of the General Clauses Act, 1897, “from” a date leaves out the first day and “to” a date includes the last day. Agreements can set their own rule.

Notice periods

Most notice periods start the day after you hand in your resignation. Say Vikram resigns on Tuesday, 20 October 2026 with a 90-day notice period. Enter 20 October 2026 as the start date and try end dates until total days shows 90, without including the end date. That end date, Monday, 18 January 2027, is his last day. If his company counts the day he resigns as day 1, he ticks Include end date and his last day is one day earlier, Sunday, 17 January 2027. Your appointment letter or HR policy decides which applies, and whether the period is in days or months.

Days between dates in Excel or Google Sheets

If you have a list of dates, a spreadsheet is quicker than checking them one by one.

• Total days: with the start date in A2 and the end date in B2, type =B2-A2. This matches the calculator without the end date.
• Working days: type =NETWORKDAYS(A2,B2). It counts weekdays and treats both dates as part of the period, so compare it with the calculator’s count with Include end date ticked. Add a range of holiday dates as a third argument to remove them too.

Limitations

• Holidays: working days are Monday to Friday only. Public holidays differ by state, bank, company and year in India, so subtract the ones that apply to you.
• Six-day weeks: if you work on Saturdays, add those back to the working day count yourself.
• No add or subtract mode: to find the date that is a set number of days away, change the end date until total days matches, as in the notice period example.
• Whole days only: the calculator ignores times of day and time zones.
• Month method: other tools may count months differently near month ends, so the months and days part can differ by a day. Total days is always the same.

To work out a share of days, such as attendance of 68 days out of 85, use our percentage calculator. For a countdown to a typing exam, pair it with practice on our typing speed test.

Key facts

• A common year has 365 days and a leap year has 366, with the extra day added as 29 February. (Britannica (opens in new tab))
• Century years are leap years only if they divide by 400, so 2000 was a leap year and 2100 will not be. (Britannica (opens in new tab))
• Under Section 9 of the General Clauses Act, 1897, the word “from” leaves out the first day of a period and the word “to” includes the last day. (India Code (opens in new tab))
• Excel’s NETWORKDAYS function returns the whole working days between two dates, leaving out weekends and any holidays you list. (Microsoft Support (opens in new tab))
• The international date standard ISO 8601 numbers the days of the week from Monday as day 1 to Sunday as day 7. (ISO (opens in new tab))