Date & Day Calculator
Count calendar days between dates, add or subtract a number of days, or compare a target date with today.
Choose a calculation
Days between dates
Find the difference from the start date to the end date, using calendar dates instead of times.
Result
Choose a start date and an end date.
Add / subtract days
Find the calendar date a chosen number of days before or after a base date.
Result
Choose a base date and enter a number of days.
Days from today
Find how many days remain until a target date, using your device’s date when this page was opened.
Result
Choose a target date.
Choose the calculation that matches your question
Use “Days between dates” for a date difference, “Add / subtract days” for a new date from a starting point, and “Days from today” for a countdown or elapsed-day check. All three modes use calendar dates, so weekends and holidays remain included.
Five days later is not five business days later
Five calendar days after September 4, 2026 is September 9. Weekends are included. To exclude weekends and company holidays, use Business Day Calculator and check whether the starting day counts. A date result alone does not establish a contractual deadline or cutoff time.
About this tool
Use this tool to calculate the number of days between two dates or find a date before or after another date. It is useful for exams, deadlines, anniversaries, and upcoming plans.
Calculations happen in your browser. The dates you enter are not saved; only the calculation mode you choose is kept in this browser for 30 days.
How the day difference is counted
The difference counts calendar-day steps: September 4 to September 9, 2026 is 5 days. The same date gives 0. This is not an inclusive count of both date labels, which would be 6 for that example; there is no inclusive-count switch.
Reversing the dates keeps the positive total and identifies the end date as earlier. Add / subtract days uses whole calendar days, including weekends and leap days. Days from today uses your device’s local date when the page opens. Times and daylight-saving clock changes do not affect the calendar-day difference.
This tool does not add months or years or exclude holidays. For a working-day schedule, check the business-day counting example and its start-date rule.
Frequently asked questions
What happens if I choose the same date?
The usual difference is 0 days.
Does it work in leap years?
Yes. Dates that include February 29 are calculated according to the calendar.
Can I calculate a number of days from today?
Yes. Choose Today as the base date in Add / subtract days, or use Days from today.
Are the start date and end date included?
It counts day steps, not both dates inclusively: September 4 to September 9 is 5 days; the same date is 0.
Do times affect the result?
No. This tool uses calendar dates only and does not use times.
Related tools
Share if this helped