How to Calculate Hours Worked (With Examples)

A shift runs from 8:30 AM to 4:30 PM, with a 30-minute unpaid lunch in the middle. How many hours does that person get paid for? Most people can eyeball this one — eight hours, minus half an hour, is 7.5. But swap in a break that overlaps two different clock-in systems, a shift that runs past midnight, or five different days that all need adding together, and the same simple subtraction starts producing wrong numbers, usually without anyone noticing until payroll runs.

This guide gives you the exact formula behind "hours worked," walks through it with a plain shift, a shift with a break, and an overnight shift, then shows how those daily totals combine into a weekly figure. If you just need a number right now, the hours calculator does the arithmetic directly; if you want to be able to check it yourself, read on.

"Hours worked" means paid time only — the stretch between clock-in and clock-out, minus any stretch inside that shift the person wasn't being paid for. A paid break (a short rest break that policy or law treats as compensated) is not subtracted, because it's still paid time; only an unpaid break, most commonly a lunch period, comes out of the total. Getting that distinction backwards — subtracting a paid break, or forgetting to subtract an unpaid one — is the single most common error in this calculation, and it shows up again in the mistakes section below.

This guide focuses specifically on turning a clock-in, a clock-out, and a break length into a number of hours. If what you actually need is the raw span between two clock times with no payroll context — no breaks, no weekly total — that narrower calculation is covered on its own in how to calculate the duration between two times.

Three steps, in order:

• Step 1 — Raw duration. Subtract the clock-in time from the clock-out time.
• Step 2 — Subtract unpaid breaks. Take away any unpaid break time inside that shift. Paid breaks are left alone.
• Step 3 — That's hours worked. What remains is the number to record for that shift.

As one line: hours worked = (clock-out − clock-in) − unpaid breaks. If the shift crosses midnight, handle Step 1 by treating the clock-out time as belonging to the next day before subtracting — covered with a full example further down — rather than letting the subtraction go negative.

Enter a clock-in time, a clock-out time, and any unpaid break minutes. The result updates as you type, in both hours-and-minutes and decimal form. It handles overnight shifts automatically — if clock-out is earlier than clock-in, it assumes the shift ran into the next day.

If that same lunch were paid rather than unpaid — some workplaces treat short breaks as compensated — Step 2 would be skipped entirely, and the result would stay at 8 hours. The break's length never changes; whether it's paid is what decides whether it's subtracted.

Overnight shifts are where the plain subtraction breaks: clock-out is a smaller number than clock-in, because the clock has wrapped around past midnight onto the next day. The fix is to treat the clock-out time as belonging to the following day before subtracting, which is the same as adding 24 hours to it first.

A weekly total is nothing more than the sum of each day's already-net hours worked. Calculate every day's figure using the same formula above — duration minus that day's unpaid breaks — and then add the daily results together. Don't subtract breaks a second time at the weekly level; they've already been removed once, day by day.

For guidance on the format a weekly timesheet is actually submitted in — which columns, how days are laid out, what a completed one looks like — see how to fill out a weekly timesheet correctly. This section is only about getting the arithmetic behind the numbers right.

• Forgetting to subtract an unpaid break — the raw clock-in-to-clock-out span isn't hours worked if any of it was unpaid.
• Subtracting a paid break by mistake — treating compensated time as if it were unpaid understates the total.
• Not rolling an overnight clock-out onto the next day — leads to a negative duration or a result exactly 24 hours off.
• Mixing 12-hour times without checking AM/PM — an 8:00 entered as PM instead of AM shifts the whole calculation by 12 hours.
• Re-subtracting breaks at the weekly level — each day's break should only ever be removed once, when that day's total is calculated.

Three things usually happen right after you know hours worked, and each has its own dedicated method rather than belonging here. Payroll systems typically store the total as a decimal — 7.5 rather than 7:30 — which is a distinct conversion covered in how to convert minutes to decimal hours for payroll. Many employers also round clock-in and clock-out times to the nearest interval before this calculation even starts, under rules explained in timesheet rounding and the 7-minute rule. And once a weekly total crosses a certain threshold, a separate overtime rate applies to the hours above it, which is worked through in how to calculate overtime hours and pay.