**The concept of time**

Time is a concept to describe the sequence of events, events and their duration. Time is determined by the number of movements of repeating objects (the quantification of repetitive movements) and usually has a milestone associated with a certain event.

Time is calculated by year, month, week, day, hour, minute, second, count. In which, the base unit is "day", a day is divided into 24 hours (12 watch hours - the usual calculation in ancient times), 1 hour is divided into 60 minutes, 1 week includes 7 days, 1 month includes 28 to 31 days depending on the month of the year, ...

**Unit for measuring time**

Other common time units are defined on the basis of the second concept:

One minute has 60 seconds

One hour has 60 minutes

one day has 24 hours

A week has 7 days

A month has 4 weeks + 0, 1, 2, 3 days, (average 30.4 .. days)

A year is the average length of the Earth's cycle around the Sun, consisting of 12 months, or 52 weeks a day, or 365 days and 6 hours.

**Time calculator**

Use this calculator to add or subtract times (days, hours, minutes, seconds) from the start date and time. The result will be the new date and time based on the time subtracted or added. To calculate the amount of time (day, hour, minute, second) between times of two different dates, use the Duration Calculator.

Use this calculator to add or subtract two or more time values as one expression. The accepted input has d, h, m, and s following each value, where d means day, h means hours, m means minutes, and s means seconds. The only operators accepted are + and -. "1d 2h 3m 4s + 4h 5s - 2030s" is an example of a valid expression.

Calculation will be performed immediately after the operation is selected. You can increase or decrease the hour, minute, and second values of time using the up and down keys on the keyboard. The Now button sets the start time to the current time. And clearly reset input button times.

This is our site that introduces Online Time Calculator. This is a great and efficient online tool to calculate the time remaining up to a certain time or calculate the exact amount of time between two specified times. Use the Online Time Calculator and can be a great help for anyone who needs to do this kind of computation related to scientific work, research, some daily activities, etc. In addition, there is some very useful information about the time units and the specifics of the transitions between them.