Time Calculator

Time uses base 60: 60 seconds make a minute and 60 minutes make an hour. To add times by hand, add each unit separately, then carry over: every 60 seconds becomes 1 minute, and every 60 minutes becomes 1 hour.

Example: 2 h 45 min + 1 h 30 min = 3 h 75 min = 4 h 15 min.

When subtracting a longer time from a shorter one, the result is negative. The hours, minutes, and seconds show the size of the difference, and the totals show the minus sign.

Timesheets and payroll often use decimal hours. Divide minutes by 60 and seconds by 3,600, then add them to the hours:

• 15 minutes = 0.25 hours
• 30 minutes = 0.5 hours
• 45 minutes = 0.75 hours
• 4 h 15 min = 4.25 hours

Multiply decimal hours by an hourly rate to get pay. For example, 4.25 hours × $20/hour = $85.