How to use this calculator
Use the time card calculator with breaks to turn dated shifts into a period total. Each row records a date, start, end, unpaid break, and whether the end is on the next day. Choose the work location before reviewing the result: this calculator measures actual elapsed time in that time zone, including supported daylight saving changes.
Start with the example week, then replace or remove its rows to match your records. Add another row for a split shift on the same date. The calculator shows row validation, daily totals, and ISO weekly totals. An optional hourly rate gives a flat-rate gross estimate, while printing and CSV export provide a record you can check outside the browser.
Formula and calculation method
Net shift seconds = end instant − start instant − unpaid break minutes × 60. Period hours = sum of valid shift seconds ÷ 3,600.
Calculate every row independently
A row’s date and location turn the clock readings into actual instants. The next-day checkbox moves the end into the following date. The break deduction is then applied to the elapsed span. Check each row before relying on a total; the interface flags invalid rows and prevents an incomplete period from being presented as a usable final total.
Group hours without inventing pay rules
Daily totals group shifts by their recorded start date, and weekly totals use ISO week-year and week numbers. Those groups are helpful for review but are not a configurable employer workweek. The optional rate multiplies all net hours by one rate. Use the separate overtime calculator when you need a regular and premium breakdown for one defined workweek.
Worked examples
A 40-hour week
Five shifts from 09:00 to 17:30 have a gross duration of eight and a half hours each. Deduct 30 unpaid minutes per shift to get eight net hours per day. The five shifts total 40 hours. Remove the unused weekend rows or leave their zero-duration values when reproducing the example.
Two intervals in one day
Record 08:00–12:00 in one row and 13:00–17:00 in another row on the same date. Each contributes four hours, for eight hours in total. The hour between the intervals is already excluded, so entering an additional 60-minute unpaid break would double-deduct lunch. Keep a separate label for each interval if helpful.
Overnight work with an unpaid break
A 22:00–06:00 shift on an ordinary night lasts eight hours when next day is selected. With a 30-minute break it contributes 7.5 hours. The same readings near a clock transition can produce a different elapsed span. Use the actual shift date and location rather than replacing the date with a convenient example week.
Edge cases and practical checks
Overlaps and repeated clock readings
Overlapping rows are rejected unless you explicitly allow both to count, because duplicated time can inflate the result. A local time during the fall clock change may occur twice; expand the row’s clock-change options to select the first or second occurrence for each endpoint. Do not choose an occurrence simply to force a preferred total.
Period limits and export checks
You can enter up to 62 shifts across 31 dates. Review the date, location, next-day flag, and break in the exported record. An overnight row is attributed to its start date rather than split at midnight, which matters when comparing daily summaries with another system. Saved presets are optional and remain separate from the printed record.
Frequently asked questions
Does the time card subtract lunch automatically?
No. Enter the unpaid minutes for each shift. If you split a day into morning and afternoon rows, the gap is already outside the recorded work intervals. Deduct only breaks contained inside a row so the same absence is not subtracted twice.
Can I calculate pay with this time card?
An optional hourly rate multiplies the net period hours by one flat rate. It is a gross arithmetic estimate without overtime tiers or deductions. The dedicated Time Card Calculator with Pay Rate offers a more focused single-workweek view with an editable overtime threshold and multiplier.
How do I enter an overnight shift?
Use the date on which the shift starts and check the row’s next-day option. Leave the finish time as its actual morning clock reading. The selected time zone determines elapsed time, including any clock change between the two endpoints.
Why does a row show a clock-change warning?
Some local times repeat or do not exist when a location changes its clock. The calculator needs an unambiguous instant to measure elapsed hours. Review the original record and select an occurrence where appropriate; an ambiguous clock reading alone cannot settle the question.
Can I print or download the results?
Yes. Print uses your browser’s print dialog, and CSV export creates a spreadsheet-friendly record when the rows are valid. Before using either output, check for errors and confirm the work location. Keep the original shift records if you need an audit trail.
Are weekly totals the same as payroll overtime weeks?
Not necessarily. This page groups by ISO weeks, while an employer’s workweek can have a different starting day and time. An overnight shift also stays with its start date here. Use records aligned to the actual workweek when calculating overtime.
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