Calculation Methodology

Every clock time becomes a whole number of minutes after 12:00 AM, from 0 to 1439. Every duration is a whole number of minutes, so totals never drift from rounding.

minute of day = hour × 60 + minute
12:00 AM = 0 · 12:00 PM = 720

A shift is same-day unless you turn on “Ends next day”. HourCalio never guesses that a shift crossed midnight.

Equal start and end times give 0h 00m, or 24h 00m when “Ends next day” is on. One shift cannot exceed 24 hours.

duration = end − start
with Ends next day: duration = (24h − start) + end

The unpaid break is subtracted from the shift. A break longer than the shift is an error, not a negative result. A break equal to the shift gives 0h 00m.

worked = shift length − unpaid break

Daily worked times are added. In a biweekly card, days 1–7 are Week 1 and days 8–14 are Week 2, whatever their weekday names, and each week has its own subtotal.

week total = Σ daily worked
period total = Week 1 + Week 2

Overtime is any weekly total above your threshold. The defaults, 40h 00m and a 1.5× multiplier, are editable settings. Each week is evaluated on its own and never averaged across two weeks.

The defaults follow the general federal rule of the Fair Labor Standards Act (FLSA): covered, non-exempt employees receive at least one and a half times their regular rate for hours over 40 in a workweek. HourCalio multiplies the hourly rate you enter; it does not work out a regular rate that includes bonuses or other pay.

The result is an estimate. It does not determine coverage, exemptions, state rules, agreements or wages that are legally owed.

overtime = max(0, week total − threshold)
regular = week total − overtime

Pay is an estimate before taxes and deductions. Each pay component is calculated from exact minutes and rounded half-up to the cent; hours are never rounded to two decimals first. HourCalio does not calculate net pay.

regular pay = round(regular minutes × rate ÷ 60)
overtime pay = round(overtime minutes × rate × multiplier ÷ 60)
estimated gross pay = regular pay + overtime pay

Minutes are divided by 60 and shown with two, three or four decimal places, rounded half-up. Converting decimal hours back to minutes rounds to the nearest minute. 7:30 is not 7.30: 0.30 hours is 18 minutes.

decimal hours = total minutes ÷ 60
total minutes = round(decimal hours × 60)
7h 30m = 7.50 · 7.58 h = 7h 35m

12:00 AM is 0000 and 12:00 PM is 1200. Results always use four digits, so 12:30 AM is 0030. 2400 is not accepted.

2:35 PM → 1435 · 14:35
0000 → 12:00 AM

Calculations run in your browser. HourCalio does not send calculator values to its servers.

Saving a time card is opt-in and stays on your device. A saved time card is removed 90 days after it was last saved, or earlier if you clear it.

Every formula is checked against the canonical examples of the HourCalio calculation specification, and every example shown on this site is recalculated by an automated test before each release.

• 42h 30m → 2h 30m overtime
• $1,000.00 + $93.75 = $1,093.75
• 10:30 PM → 6:15 AM next day = 7h 45m

The overtime defaults and their limits are based on these U.S. Department of Labor pages, consulted on September 29, 2026.

• Fair Labor Standards Act overview (U.S. Department of Labor)
• Overtime Pay (U.S. Department of Labor)

Last reviewed: September 30, 2026. Each change to a formula, rounding rule, default or limit is added here with its date.

September 30, 2026 — First version: six calculators, weekly overtime by fixed seven-day workweek, half-up rounding to the cent, and opt-in saving of time cards on your device.