Why your timesheet says 7.75: decimal hours, explained

Themes: Hours & pay23 October 2026·5 min read·By David Lawrence

You worked from 9:00 to 17:15 with half an hour for lunch. That's 7 hours and 45 minutes. Then the timesheet, the payroll system or the invoice asks for your hours, and the number it wants is 7.75.

Most of our posts so far have been about rest and wellbeing. This one starts a more practical thread, on the numbers behind your hours and your pay. And the first number to get right is the one with the dot in it.

How decimal hours work

An hour has 60 minutes, but a decimal has 100 hundredths. Decimal hours turn the minutes into a fraction of an hour so that payroll and spreadsheets can add them up and multiply them by a rate like any other number.

To convert, divide the minutes by 60:

• 15 minutes is 15 ÷ 60 = 0.25
• 30 minutes is 0.5
• 45 minutes is 0.75
• 20 minutes is 0.33, and 40 minutes is 0.67
• 6 minutes is exactly 0.1, which is handy for checking

So 7 hours 45 minutes is 7.75 hours, and 7.75 × $20 an hour is $155. Going the other way, multiply the part after the dot by 60: 0.4 × 60 is 24, so 8.4 hours is 8 hours 24 minutes. The decimal hours converter does both directions and has a chart for every minute from 1 to 60.

The mistakes that cost you minutes

The format causes a few mistakes, and most of them go against the person who did the work.

1. Writing the clock time as a decimal. 7 hours 30 minutes typed as "7.30" is read as 7.3 hours, which is 7 hours 18 minutes. You've lost 12 minutes. "7.45" is worse: it's 7 hours 27 minutes, 18 minutes short. Do that every day and a five-day week is an hour and a half short.
2. Adding hours and minutes as if they were decimals. 7:45 plus 8:20 is 16:05. Add them as ordinary numbers and you get 15.65, which is neither a time nor a correct decimal.
3. Rounding that only goes one way. Plenty of employers round to the nearest five minutes, tenth of an hour or quarter hour. That's fine if it goes both ways, but a system that always rounds your start up and your finish down takes a little from you every day.

On the third one, the US Department of Labor has spelled out the rule. Under 29 CFR 785.48(b) (opens in a new tab), rounding to the nearest 5 minutes, tenth or quarter of an hour is accepted, provided it won't, over time, result in a failure to pay employees "for all the time they have actually worked". So rounding has to average out.

Why the record matters

A wrong decimal is easy to fix if you notice it. It's much harder if nobody wrote down when you started and stopped.

In 2019, the Court of Justice of the European Union ruled on this in a case brought by the Spanish union CCOO against Deutsche Bank. The Court's press release (opens in a new tab) explains that, without a system measuring the time each worker works each day, it's not possible to determine objectively and reliably how many hours were worked, or how much overtime, which makes it "excessively difficult, if not impossible in practice" for workers to enforce their rights. The Court held that EU countries must require employers to set up an objective, reliable and accessible system for measuring the time each worker works each day, and left the details to each country.

The case also put a number on the problem. According to the Spanish court that sent the question to Luxembourg, 53.7% of the overtime hours worked in Spain weren't recorded.

Spain has since written the rule into the Estatuto de los Trabajadores (opens in a new tab) (article 34.9): employers must keep a daily record with each worker's start and finish times, hold on to it for four years and make it available to workers, their representatives and the labour inspectorate.

Habits that keep your hours straight

1. Keep the times, not just the totals. "9:02 to 17:31" can be checked later. "8.5" on its own can't. If there's ever a question, the start and finish times are what you'll want.
2. Convert at the end, and only once. Record in hours and minutes during the week and convert the weekly total, or use a tool that does it for you. Typing decimals by hand every day is how 7.30 sneaks in.
3. Read the decimal back. Before you submit, look again at anything ending in .30, .45 or .50. Each is a real decimal, but it's also what a clock time looks like when it's typed in the wrong format.
4. Find out how your employer rounds. Ask whether they round, to what and in which direction. Then compare your own record with your payslip now and again.
5. Keep unpaid breaks separate. Only unpaid breaks come off your hours. The time card calculator takes start, finish and unpaid break for each day and gives you the week in hours and minutes and in decimal.

Where Clockflux fits in

Clockflux records the time you check in and out, and shows your totals in either format. The small button next to today's total switches between decimal hours (7.75) and hours and minutes (7:45). One thing to know: the decimal view rounds each day to the nearest quarter hour, so 7 hours 50 minutes shows as 7.75. The hours and minutes view is exact to the minute. Both are explained in tracking your hours.

With Clockflux Pro, you can export your entries as CSV or as a PDF report for any date range. Each day lists its sessions with their start and finish times, and its total in decimal hours to two decimal places, without the quarter-hour rounding. That's the kind of record you can check a payslip against, or hand over if your hours are ever questioned.

If you'd rather keep track on paper or in a spreadsheet, how to track your work hours walks through a simple routine, and how to calculate overtime picks up where this post leaves off.