Time Calculator

Add or subtract hours, minutes, and seconds from a clock time.

11:15:00
resulting clock time

Same day

How to use time calculator

  1. Choose a clock time
  2. Enter the duration and choose add or subtract
  3. Check the new time and day offset

Worked example

23:30 + 2 hours 15 minutes

01:45, next day

How the result is calculated

Convert the clock and duration to seconds, add or subtract, then separate full days from the 24-hour clock. A day offset makes midnight crossings explicit.

Inputs stay in your browser. You can use this tool without joining the waitlist or creating an account.

From a calculation to a daily glance

Keep your next week in view.

Create a calendar event at the calculated time and view the day in your weekly widget.

  1. 1Add the events you want to see to your calendar.
  2. 2Enable that calendar in the app.
  3. 3Add Weekly Calendar; use Edit Widget → Design to choose its look.
Get early accessExplore widget designs

Web results do not automatically sync to the app. Setup is manual; calendar events appear through your enabled calendars.

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CelebrationWorkshopMeetingProject reviewTeam dinner
Weekly Calendar · example design from the app

Frequently asked questions

How does this time work?
Convert the clock and duration to seconds, add or subtract, then separate full days from the 24-hour clock. A day offset makes midnight crossings explicit.
How can I use the result with Monthly Calendar Widgets?
Create a calendar event at the calculated time and view the day in your weekly widget.
Do I need an account to use this tool?
No. The tool works in your browser without an account. Your inputs are not sent to our servers. Downloaded files stay on your device.

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