Time Tracking Calculator
Adds up timesheet entries in any format, shows the decimal and clock totals, and says what the rounding rule adds over a week and a year.
Entries 5
Rounding up to the next quarter hour
Break deducted 30 minutes an entry
09:15-17:30 7:45 = 7.75 h
08:50-16:05 6:45 = 6.75 h
7:38 7:08 = 7.13 h → billed 7:15
6.4 5:54 = 5.90 h → billed 6:00
09:00-18:12 8:42 = 8.70 h → billed 8:45
Total, exact 36:14 = 36.23 hours
Total, as billed 36:30 = 36.50 hours
the rounding adds 0:16, 0.74%
an entry, on average 3.2 minutes
The two formats
hours and minutes 36:30
decimal hours 36.5000
the trap writing 36:30 as 36.30 loses 12.0 minutes
Pay
36.50 h at $85.00 $3,102.50
total $3,102.50
of which rounding $22.67
over a 48-week year $1,088.00 if this is a typical week
The same hours under every rule
exact, to the minute 36:14
nearest tenth of an hour, 6 minutes 36:18, 0:04 more
nearest quarter hour 36:30, 0:16 more
up to the next quarter hour 36:30 ← yours
up to the next half hour 37:30, 1:16 more
up to the next hour 38:00, 1:46 more
7:45 is 7.75 hours, not 7.45. Writing the minutes after the decimal
point is the commonest timesheet error and it loses 30 minutes on that
entry alone: over a year of five-day weeks that is about three working
days.
Rounding to the up to the next quarter hour adds 0:16 across 5 entries,
which is 3.2 minutes an entry on average.
Nearest-quarter rounding is fair over many entries: it rounds down as
often as up. Always-up rounding is not, and it adds 7.5 minutes an entry
on average, so a day with six entries bills 45 minutes nobody worked.
Which rule is in use is a contractual question rather than an arithmetic
one.
The number of entries matters more than the rule. One entry a day
rounded up to the quarter is trivial; rounding every task separately
turns the same day into an hour of uplift, which is why per-task
rounding is worth arguing about and per-day rounding usually is not.
In several jurisdictions rounding employee time is only lawful if it is
neutral over time. Rounding that systematically favours the employer is
a wage claim in the United States and in parts of the EU, and "everyone
does it" has not been a successful defence.
Breaks are deducted before rounding here, which is the order that
matters: rounding first and then deducting a 30 minute break gives a
different answer, and the difference compounds across a week.
Overtime rules are jurisdictional and this applies a flat threshold.
Daily thresholds, weekly thresholds, the seventh consecutive day and
double time past a second threshold all exist somewhere, and none of
them is derivable from the hours alone.
Tracking time to the minute and billing to the quarter hour is a
reasonable combination: the record is accurate, the invoice is simple,
and the client can see both. Tracking to the quarter hour destroys the
information before anybody has looked at it.
Output is valid and updates as you type.
Fix the highlighted fields to update the output.
7:45 is 7.75 hours. Writing it as 7.45 loses eighteen minutes, and doing that daily costs about three working days a year.
That is the first half of timesheet arithmetic. The second half is rounding, and it is not neutral. Rounding each entry up to the next quarter hour adds 7.5 minutes an entry on average, so a day with six entries bills 45 minutes nobody worked. On the week below, always-up rounding adds 16 minutes, which is $23 at $85 an hour and $1,088 over a working year.
Nearest-quarter rounding is fair over many entries. Always-up is not, and which one is in use is a contractual question rather than an arithmetic one.
How to use
- Put the entries in, one a line. A range like
09:15-17:30, a duration like7:38, or a decimal like6.4. - Pick the rounding rule your client or employer actually uses.
- Read the comparison across every rule at the bottom.
Example
Five days, half-hour unpaid break, rounded up to the quarter:
09:15-17:30 7:45 = 7.75 h
08:50-16:05 6:45 = 6.75 h
7:38 7:08 = 7.13 h → billed 7:15
6.4 5:54 = 5.90 h → billed 6:00
09:00-18:12 8:42 = 8.70 h → billed 8:45
Total, exact 36:14 = 36.23 hours
Total, as billed 36:30 = 36.50 hours
the rounding adds 0:16, 0.74%
an entry, on average 3.2 minutes
The two formats
hours and minutes 36:30
decimal hours 36.5000
the trap writing 36:30 as 36.30 loses 12.0 minutes
Pay
36.50 h at $85.00 $3,102.50
of which rounding $22.67
over a 48-week year $1,088.00 if this is a typical week
The same hours under every rule
exact, to the minute 36:14
nearest tenth of an hour, 6 minutes 36:18, 0:04 more
nearest quarter hour 36:30, 0:16 more
up to the next quarter hour 36:30 ← yours
up to the next half hour 37:30, 1:16 more
up to the next hour 38:00, 1:46 morePitfalls
Minutes are not decimals. 30 minutes is 0.5 hours, not 0.30. Divide minutes by 60, and if a spreadsheet is involved, store the duration as a proper time value or as a decimal, never as the digits of the clock.
The number of entries matters more than the rule. One entry a day rounded up to the quarter is trivial. Rounding every task separately turns the same day into an hour of uplift, which is why per-task rounding is worth arguing about and per-day rounding usually is not.
Deduct breaks before rounding. Rounding first and then deducting a 30 minute break gives a different answer, and the difference compounds across a week. This deducts first.
Non-neutral rounding is a legal question in some places. In the United States and parts of the EU, rounding employee time is only lawful if it is neutral over time. Systematically favouring the employer is a wage claim, and “everyone does it” has not worked as a defence.
Track to the minute, bill to the quarter. That combination keeps the record accurate, the invoice simple, and lets the client see both. Tracking to the quarter destroys the information before anyone looks at it.
Overtime rules do not come from the hours. Daily thresholds, weekly thresholds, the seventh consecutive day, double time past a second threshold: all exist somewhere, and this applies one flat threshold to the total. Check the rule that applies to you.
A shift crossing midnight is not negative. 22:00-06:30 is eight and a half hours, which this handles.
A spreadsheet subtracting the two times gives a negative number and often shows ####.
Compatibility
Arithmetic in the browser: nothing is uploaded and nothing is stored, which matters for someone else’s hours.
Entries are accepted as a range, a clock duration or a decimal, mixed freely in the same list. A range whose end is earlier than its start is treated as crossing midnight. Minutes above 59 in a clock duration are refused rather than silently converted.
Breaks are deducted per entry before rounding. The rounding rules are exact-to-the-minute, nearest tenth of an hour, nearest quarter, and up to the next quarter, half hour or hour, and every one of them is applied to the same entries at the bottom so the differences are arithmetic rather than assertion.
The annual figure assumes 48 working weeks, which leaves room for holiday, and it is there to make a small weekly number legible rather than to be precise about your year.