1. Net Shift Duration & Midnight-Crossover Equation
For each daily shift $i$ with clock-in time $T_{\text{in}}$ (in minutes from 00:00), clock-out time $T_{\text{out}}$, and unpaid bona fide meal break $B_i$ (in minutes):
RawNetMins(i) = max(0, RawShiftMins(i) - B_i)
Adding 1440 minutes (24 hours) whenever $T_{\text{out}} < T_{\text{in}}$ ensures that overnight graveyard shifts (for example, 22:00 to 06:30) accurately evaluate to 510 raw minutes minus break time, without requiring users to enter multi-day calendar dates.
2. Timeclock Rounding Algorithms (29 CFR § 785.48(b))
Under 29 CFR § 785.48(b), employers are permitted to round employee punch times to the nearest 5 minutes, one-tenth of an hour (6 minutes), or quarter-hour (15 minutes), provided the arrangement averages out over time and does not systematically fail to compensate employees for time worked. Our engine computes both exact minutes and rounded minutes:
• FLSA 15-Min: NetMins(i) = round(RawNetMins(i) / 15) * 15 [1–7m rounds down; 8–14m rounds up]
• 1/10th Hr (6m): NetMins(i) = round(RawNetMins(i) / 6) * 6
• Nearest 5-Min: NetMins(i) = round(RawNetMins(i) / 5) * 5
• Decimal Hours: DecHrs(i) = NetMins(i) / 60.0
The Rounding Audit Differential displayed in the Wage Protection Bar is calculated as:
RoundingDiffPay = RoundingDiffHrs * BaseHourlyRate
3. Federal FLSA Overtime Model (29 CFR § 778.101)
Under the federal Fair Labor Standards Act (FLSA), non-exempt employees must receive overtime compensation at a rate not less than one and one-half times (1.5x) their regular rate of pay for all hours worked in excess of 40 hours in a single 7-day workweek. For bi-weekly (14-day) periods, each 7-day workweek is evaluated independently (hours cannot be averaged across two weeks):
Week 2 (Days 8–14): RegHrs_W2 = min(40.0, Sum(DecHrs_8..14)), OTHrs_W2 = max(0, Sum(DecHrs_8..14) - 40.0)
4. California Daily Overtime, Double-Time & § 226.7 Meal Penalty Model
Under California Labor Code § 510, overtime is calculated on both a daily and weekly basis without pyramiding (duplicating) daily and weekly overtime hours:
- Daily Straight-Time: First 8.0 hours worked in a workday ($1.0 \times \text{Rate}$).
- Daily Overtime (1.5x): Hours worked beyond 8.0 up to 12.0 in a workday ($1.5 \times \text{Rate}$).
- Daily Double-Time (2.0x): All hours worked beyond 12.0 in a single workday ($2.0 \times \text{Rate}$).
- Weekly Overtime (1.5x): Once cumulative daily straight-time hours in a workweek exceed 40.0, any subsequent straight-time hours convert to $1.5 \times$ overtime.
- CA Labor Code § 226.7 Meal Period Premium: If an employee works more than 5.0 hours in a workday (`RawNetMins > 300`) and receives less than a 30-minute unpaid meal break (`breakMins < 30`), our engine automatically adds +1.0 hour of regular pay ($1.0 \times \text{Rate}$) as a statutory meal-period penalty.
5. Primary Public Data & Regulatory Citations
- U.S. Department of Labor (DOL) — Wage and Hour Division: 29 CFR Part 785 (Hours Worked) & 29 CFR Part 778 (Overtime Compensation).
- California Department of Industrial Relations (DIR): California Labor Code §§ 510, 512, and 226.7.
- Internal Revenue Service (IRS): Publication 15 (Circular E), Employer's Tax Guide — Social Security (6.2%) + Medicare (1.45%) = 7.65% FICA statutory employee withholding rate.