Time Calculator
By Miikka · CalcBrew · Updated
8 h 30 min
= 8.5 hours (510 minutes)
The time calculator computes the duration between two times or adds/subtracts time. Supports night shifts (times past midnight).
The Time Calculator helps you find the difference between two times or add and subtract time from a given moment. It gives you the hours and minutes without error-prone mental arithmetic.
How the calculator works and what it’s for▾
How the calculator works
To find a difference, the calculator subtracts the start time from the end time and converts the result into hours and minutes. To add time, it adds the chosen duration to the start moment and shows the new clock time.
For example, the span between 9:15 and 17:45 is 8 hours and 30 minutes. These figures are an illustrative example only.
What you enter and what you get
To calculate a difference you enter a start and end time and get the duration in hours and minutes. To add time you enter a starting time and the duration to add.
The result is either the span between two moments or a new clock time, depending on the mode you choose.
What it is used for
The calculator is handy for planning shifts, meetings, and journeys, and for working out durations when an event runs past midnight.
It suits anyone who needs a quick, accurate answer to time-based sums.
Tips for interpreting results
Remember to pick the right mode: finding a difference and adding time give different results. Check too whether the time crosses into the next day.
A clear breakdown into hours and minutes avoids the confusion that a plain decimal figure can cause.
🔄 Reviewed June 2026
Frequently asked questions
Cite this calculator
CalcBrew. (2026). Time Calculator. https://calcbrew.com/time-calculator“Time Calculator.” CalcBrew, 2026, calcbrew.com/time-calculator.Link to https://calcbrew.com/time-calculator. Results are estimates; cite the underlying formula or data source for academic work.
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