Timesheet hours total

Every ISO datetime must include either Z or an explicit offset, so records from different offices, daylight-saving periods, or overnight schedules are compared on one UTC timeline. The result also shows gross hours, total break minutes, and the number of shifts included, making the calculation easy to review or automate.

Enter complete, unambiguous shift records

Provide one row for every continuous work period. Each row needs a clock_in datetime and a clock_out datetime written in ISO 8601 form, including seconds and either Z or a numeric UTC offset such as -04:00. The offset is essential because a local wall-clock time alone does not identify one instant during timezone changes. Add break_minutes when a shift contains an unpaid break; omit it when no break should be deducted. Decimal break minutes are accepted, which is useful when a source system records fractions of a minute. A clock-out may fall on the next calendar day, so overnight work needs no special mode. The calculator rejects impossible dates, missing offsets, clock-outs that are not later than clock-ins, negative breaks, and breaks longer than their shift. It also rejects overlapping shifts after UTC normalization, because counting both would silently inflate the total. Keeping every row explicit makes the input auditable and avoids assumptions about lunch policies, rounding rules, or which gaps between shifts should count as breaks.

Understand the UTC calculation

Each timestamp is parsed as a Gregorian calendar value and converted to a UTC millisecond position using its written offset. The calculation does not consult the machine timezone, a timezone database, the current date, or any external service. For each valid row, gross duration equals the UTC clock-out instant minus the UTC clock-in instant. The entered break duration is converted from minutes to milliseconds and subtracted from that row's gross duration. Gross durations and break durations are then summed independently before the final net total is produced. This order gives stable results for teams whose entries use different offsets and for a shift that crosses midnight. Output includes total_hours for the net worked value, total_minutes for systems that prefer minutes, gross_hours before deductions, break_minutes as the combined deduction, and shift_count for reconciliation. Hour and minute values are rounded only at the output boundary to six decimal places; the internal accumulation remains in integer milliseconds. The same inputs therefore produce the same JSON regardless of browser locale or server location.

Use the result in payroll and reporting workflows

The returned fields separate source activity from the final payable duration, which helps a reviewer reproduce the arithmetic. Compare shift_count with the number of imported rows, gross_hours with the raw clock span, and break_minutes with the expected unpaid deductions before accepting total_hours. The capability deliberately does not apply overtime bands, paid-break rules, wage rates, schedule tolerances, or employer-specific rounding. Those policies vary by agreement and jurisdiction, so they should be applied in a later, clearly documented step. It also does not infer breaks from gaps between separate rows: only the break_minutes values you provide are deducted. This makes the function suitable as a deterministic building block for payroll preparation, contractor invoices, project time reports, and attendance reconciliation without embedding hidden policy. It can run free in the browser for an individual check, while API automation costs $0.002 per request. For repeatable imports, preserve the original ISO strings and offsets alongside the returned summary so any disputed total can be traced back to the exact instants and deductions used.