All guides

How to calculate hours worked for a timesheet

Timesheets and hourly invoices work in decimal hours, while clocks work in hours and minutes. Mixing the two is the most common source of wrong totals. This guide shows how to convert, how to total a week, how to treat breaks and overnight shifts, and which EU working-time rules sit in the background.

Last reviewed: 2026-10-25

The one rule: divide minutes by 60

A decimal hour is the hours plus the minutes divided by 60. Seven hours and 30 minutes is 7 + 30/60 = 7.5, not 7.30. Seven hours and 18 minutes would be 7.30. Entering clock time into a field that expects decimals silently undercounts every half hour.

Minutes to decimal hours

Values are rounded to two decimals. 15, 30 and 45 minutes convert exactly; 5, 10, 20 and so on are recurring decimals (20 minutes is 0.333…), so for billing use the rounding your contract specifies, or keep exact minutes and convert the weekly total once.

From start and end times to hours

1. Write the start and end time in 24-hour format: 08:45 to 17:15.
2. Subtract: 17:15 − 08:45 = 8 hours 30 minutes.
3. Take off unpaid breaks: 8:30 − 0:30 lunch = 8 hours 0 minutes.
4. Convert to decimal: 8.00.

If the minutes of the end time are smaller than those of the start time, borrow an hour: 17:10 − 08:45 is 16:70 − 08:45 = 8 hours 25 minutes = 8.42.

Overnight shifts

When a shift crosses midnight, add 24 hours to the end time before subtracting. A shift from 22:00 to 06:30 is (06:30 + 24:00) − 22:00 = 8 hours 30 minutes = 8.5. Record the shift on the day it started, and say so in the notes, so it is not counted twice.

A worked week

This is exactly what the timesheet generator adds up when you enter the decimal column: 8 + 7.5 + 8.25 + 8 + 6.75 = 38.5 hours. To bill it, multiply by your hourly rate: at 30.00 an hour, 38.5 × 30.00 = 1,155.00. In the invoice generator, put 38.5 in the quantity and 30.00 in the unit price.

Breaks: in or out?

Whether breaks count as working time depends on your contract and national law. As a rule, unpaid breaks are left out of the hours, and paid breaks (where the employer pays for them) stay in. At EU level, the Working Time Directive as summarised by the Your Europe portal says that if employees work more than 6 hours a day, they must be given a break; the length is usually set by collective agreements or national law.

EU working-time limits to keep in mind

According to Your Europe, employers in the EU must ensure that staff:

• do not work more than 48 hours per week on average, including overtime (averaged over a reference period of up to 4, 6 or 12 months depending on national rules);
• get at least 11 consecutive hours of daily rest in any 24-hour period;
• get a break when working more than 6 hours a day;
• get at least 24 hours of uninterrupted weekly rest in each 7-day period (over a two-week reference period);
• if they are night workers, do not work more than an average of 8 hours per 24 hours.

National rules or collective agreements can be more favourable to workers. A timesheet that shows a 60-hour week or a 9-hour gap between shifts is a signal to check what applies.

Who has to record hours?

In May 2019 the Court of Justice of the EU ruled (case C-55/18) that Member States must require employers to set up a system enabling the duration of daily working time to be measured. How that is done is up to each country, so many employers have their own time-recording system. A PDF timesheet is useful for freelancers, contractors and small teams, and as an attachment to an hourly invoice, but if your employer has an official system, that is the record that counts.

Common mistakes

• Typing 7.30 for seven and a half hours (it should be 7.5).
• Counting the lunch break when it is unpaid.
• Rounding each day up to the next quarter hour without an agreement, which adds up over a month.
• Filling in a month at once from memory instead of daily.
• Recording an overnight shift on both days.

Fill in a timesheet

Frequently asked questions

Sources: Your Europe — Working hours (EU rules for employers) · Court of Justice of the EU — Press release 61/19, case C-55/18