Add two time durations together. Perfect for calculating total work hours, travel time, or project durations.
Last updated: March 2026
Hours
Minutes
Seconds
Hours
Minutes
Seconds
An add time calculator adds two time durations together and converts the result into clean hours, minutes, and seconds. It is useful when normal decimal addition is awkward because time rolls over at 60 seconds and 60 minutes.
For example, 2h 30m 15s plus 1h 45m 50s does not stay as 3h 75m 65s. The extra seconds roll into minutes, and the extra minutes roll into hours.
Common uses:
The safest way to add time is to convert both durations into total seconds, add them together, then convert the result back into hours, minutes, and seconds.
Total seconds = hours × 3600 + minutes × 60 + seconds
Once the total seconds are known, the calculator divides by 3600 to get hours, uses the remainder to get minutes, and leaves the final remainder as seconds.
Add the first duration using the hours, minutes, and seconds fields. Leave any unused field as 0.
Add the second duration. The calculator accepts hours, minutes, and seconds separately so the result can be normalized correctly.
Press calculate to get the final time in hours, minutes, and seconds. The calculator also shows total hours and total minutes.
Input:
Calculation:
The calculator keeps minutes and seconds within 0 to 59 before calculating. If you need to add 90 minutes, enter it as 1 hour and 30 minutes.
Seconds make the math clean. Once both durations are converted to seconds, they can be added normally and then converted back into hours, minutes, and seconds.
Yes. It works well for adding two work sessions, task durations, shift blocks, or billable time entries.
No. This calculator is for adding positive time durations. For subtracting durations, use a time duration or hours and minutes calculator.
Total hours shows the full duration as a decimal. For example, 4h 30m equals 4.50 total hours.
Total minutes shows the full duration converted into minutes, rounded down to whole minutes when seconds are present.
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