Date Time Add/Subtract Calculator – Free Online Tool
Add or subtract time durations and calculate future/past dates with precision. Free online date time calculator for project planning and scheduling.
Date Time Add/Subtract Calculator – Free Online Tool
Mode
Time Mode
Operation
Add
Input Mode
Picker
Time 1You can paste time formats like HH:MM:SS, HH:MM, or MM:SS
Time 2You can paste time formats like HH:MM:SS, HH:MM, or MM:SS
How to Use
Add or subtract time durations and calculate future/past dates with precision.
Choose the mode (Time or Date) and operation (add or subtract)
Enter the first time/date
Enter the second time/days to add or subtract
Click Calculate to see the result
Main Features
Add and subtract time durations
Calculate future and past dates
Support for hours, minutes, and seconds
Multiple input formats (manual and picker)
Copy results to clipboard
Free and easy to use
Use Cases
Calculate project deadlines
Plan travel return dates
Track rental periods
Calculate work hours and overtime
Plan event countdowns
Calculate subscription renewals
Frequently Asked Questions
Common questions about date and time calculations.
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