Time Duration Calculator

One shift, measured properly

This page answers the everyday form of "how long was that?": a start time, an end time, minus an unpaid break, with the answer in both hours-and-minutes and decimal hours. It shines where the times are not friendly round numbers and where a shift crosses midnight, which is where manual subtraction starts producing negative numbers and quiet errors.

It is deliberately a single-shift tool. Summing a week of shifts on one page is the job of the Time Card Calculator, which processes lines like this one and adds the pay if you enter a rate. Neither tool handles legal rules — overtime thresholds, minimum daily hours, rounding policies chosen by an employer — so treat those as a layer you apply afterwards with your own contract and local law.

A worked example, step by step

Problem: a night shift runs 22:15 to 06:00 the next morning with a 45-minute unpaid break. How long was actually worked?

1. Total span: 22:15 → 06:00 is 7 h 45 m (the tool adds the next day when the end is earlier).
2. Minutes form: 7 × 60 + 45 = 465 minutes on the clock.
3. Subtract the break: 465 − 45 = 420 minutes.
4. Back to hours: 420 ÷ 60 = 7 h 00 m, decimal 7.00.

For payroll, the 7.00 is the figure the timesheet wants. If the shift had been 22:15 to 05:45 the span would be exactly one hour shorter, and the tool shows both the span and the net so you can see the break's effect line by line.

Minutes to decimal hours

Decimal hours are minutes ÷ 60. Common values:

The reverse trips people up: 7.30 decimal hours is 7 h 18 m, not 7 h 30 — decimals are a fraction of an hour, not a minutes field.

Mistakes around shift maths

• Entering the break as hours. The field wants minutes: one hour is 60, three and a half hours is 210.
• Writing 7.30 for seven and a half hours. Decimals divide by 100, minutes are a running clock. Use the tool's decimal display to stay consistent.
• Avoiding the midnight problem by hand. Manual subtraction goes negative after midnight; the tool handles the day rollover when end earlier than start.
• Forgetting unpaid breaks are policy-specific. A paid 15-minute break must be entered as a zero break, not 15.
• Mixing 12-hour times without am/pm. Prefer the 24-hour form (14:30) to avoid half the day's confusion.

Keep exploring

• Time Card Calculator — many shifts per week, with pay.
• Working Days Calculator — weekdays between dates for leave and deadlines.
• Hourly to Salary Calculator — turn solved hours into weekly and yearly pay.