Free calculators and unit converters for general and everyday use.
Our online tools will provide quick answers to your calculation and conversion needs. On this page, you can count any number of hours or minutes from a given time. Get answer to questions like "what time will it be if you were to add two hours and forty minutes to the current time?"
To find time duration between two time values in hours, minutes and seconds, use our time interval calculator.
Android: Use this time calculator offline with our all-in-one calculator app.
Before we start the calculation, we convert the time value to 24-hour format.
Steps for adding timeAdd the hours and the minutes separately. If the minutes are >= 60, subtract 60 from the minutes and add 1 to hours. If the hours are >= 24, set hours to "hours mod 24".
Steps for time subtractionSubtract the hours and the minutes separately. If the minutes are <= 0, add 60 to the minutes and subtract 1 from hours. If the hours are <= 0, add 24 and set it to "hours mod 24".
Convert the time back to 12-hour format at the end of calculation.