Date & Time Calculator
Add Time Calculator
Add hours, minutes and seconds to a starting time.
Calculator
Results
Result time
16:15:30
Total added minutes345.5
Next-day rolloverNo
24-hour format16:15:30
Results are calculated instantly in your browser using the inputs shown. Date and time calculations follow the stated assumptions below.
How it works
Add hours, minutes and seconds to a starting time.
Result = starting time + added hours + minutes + seconds, wrapping at midnight.
Example
| Example | Result |
|---|---|
| 10:30 + 5:45:30 | 16:15:30. |
Important notes
- Calendar calculations use Gregorian calendar rules.
- Business-day calculations exclude Saturday and Sunday unless stated otherwise.
- Time-zone calculations depend on the browser's IANA time-zone data.
- For planning purposes, verify dates and times when a contractual or legal deadline is involved.
Frequently Asked Questions
Does it show the next day?
Yes, the result is wrapped to 24-hour clock time and the rollover is indicated.
How to use this calculator
What to enter
Enter or select the following as requested: Starting time; Hours; Minutes; Seconds. Follow the units, valid ranges, examples, and options displayed beside each field.
What the result means
The date or duration result is calculated from the entered dates, times, calendar rules, and exclusions. Check inclusive versus exclusive counting, time zone, daylight-saving changes, and whether weekends or holidays are excluded.
When to use it
Use this to plan a date, measure elapsed time, or estimate a deadline. Verify the relevant calendar, location, and legal or workplace rules when they affect the answer.