Time calculator
To add times, convert everything to seconds, add, and convert back: 1:45:30 + 2:30:45 = 4:16:15. You can also find the duration between two clock times, such as a shift from 22:30 to 06:15 (7 h 45 min).
- ๐ Runs on your device
- โค 0 bytes uploaded
- ๐ด Works offline
- โ Free, no sign-up, no watermark
How to use Time Calculator
- Enter the hours, minutes and seconds of each time.
- Choose + or โ for each one and add more rows if you need them.
- Read the total in h:mm:ss and in decimal hours.
- For a duration, enter a start and an end clock time below.
Is it private?
Yes. Time Calculator runs entirely in your web browser. What you type is never sent to Nolo or anyone else, and the page cannot send it anywhere: its security policy only allows it to talk to nolotools.com, which has no place to receive data. Nothing is stored either: close the page and it is gone. How Nolo works.
Questions and answers
How do I add hours and minutes?
Add minutes to minutes and hours to hours; every 60 minutes carries over to an hour. The calculator does this for seconds too.
How do I convert minutes to decimal hours?
Divide by 60. 45 minutes = 0.75 hours, so 7 h 45 min = 7.75 hours. Timesheets often need this.
What if the end time is past midnight?
If the end time is earlier than the start time, the calculator assumes it is the next day and adds 24 hours.
Can the total be negative?
Yes. If you subtract more than you add, the total is shown with a minus sign.
Are my numbers sent anywhere?
No. Everything is calculated in your browser with JavaScript. Nothing you type is uploaded, stored on a server or tracked, and the calculator works offline once the page has loaded.