Night, evening and weekend work often comes with a premium — a shift differential. It looks simple, a couple of dollars more per hour, but it has a second effect many paychecks get wrong: under federal overtime rules, the differential raises your regular rate, so every overtime hour in that week is worth more too. This calculator shows both the differential itself and the overtime it carries with it.
How to use the shift differential calculator
- Enter your base hourly rate.
- Choose whether the differential is dollars per hour or a percentage of the base rate, and enter the amount.
- Enter the total hours worked this week and how many of them earn the differential.
- Check the overtime threshold (40 hours under federal law) and multiplier (1.5 for time and a half).
- Read the gross pay, the regular rate and how much extra overtime the differential produced.
Shift differential formulas
Straight time for overtime hours is already in the straight-time figure, so only the extra half (the premium) is added for those hours. This is the method in the Department of Labor’s regular-rate regulations (29 CFR Part 778).
Worked example
Base rate $22.00, differential $2.50/h, 46 hours worked, 30 of them on night shifts.
Straight-time pay = 46 × $22.00 + 30 × $2.50 = $1,012.00 + $75.00 = $1,087.00.
Regular rate = $1,087.00 ÷ 46 = $23.63. Six hours are overtime, so the premium is 0.5 × $23.63 × 6 = $70.89.
Gross pay = $1,157.89. Without the differential the week would pay $1,078.00, so the differential is worth $79.89 — $75.00 directly plus $4.89 of extra overtime.
Typical differential amounts
Differentials vary widely by industry and region. A few common structures:
| Structure | Example | Hourly effect at $22 base |
|---|---|---|
| Flat evening premium | $1.00/h for 3 p.m.–11 p.m. | $23.00 |
| Flat night premium | $2.50/h for 11 p.m.–7 a.m. | $24.50 |
| Percentage night premium | 10% of base | $24.20 |
| Weekend premium | 15% of base | $25.30 |
| Stacked night + weekend | 10% + 15% | $27.50 |
Health care, manufacturing, warehousing and public safety use differentials most often. Some employers pay the premium for the whole shift if most of it falls in the qualifying window; others pay only for the hours inside it.
Things to check on your pay stub
Overtime rate
If your stub shows overtime at exactly 1.5 × your base rate in a week with differential hours, the overtime may be underpaid. The required rate is 1.5 × the weighted regular rate, which is higher.
Hours that qualify
Write down which hours earned the premium. Overnight shifts that start before and end after midnight are easy to misclassify, especially across a workweek boundary.
Salaried and exempt staff
Exempt employees are not owed overtime, so the differential is simply extra pay. Non-exempt salaried employees are still covered by the regular-rate rules.
This calculator estimates gross pay before taxes and deductions. State laws can add daily overtime or other rules; check with your employer or your state labor department for your situation.
For overtime without a differential, use the overtime calculator or the simpler time and a half calculator. Holiday premiums follow different crediting rules, covered by the holiday pay calculator. To plan which days you will work nights, the shift pattern calculator lays out rotating schedules.
Frequently asked questions
What is a shift differential?
It is extra pay for working less desirable hours, such as evenings, overnight shifts or weekends. It may be a flat amount per hour (for example $2.50) or a percentage of the base rate (for example 10%). Federal law does not require it; it comes from employer policy or a union contract.
Does a shift differential affect overtime pay?
Yes. Under the Fair Labor Standards Act, shift differentials are part of the regular rate of pay (29 CFR 778.207). Overtime must be paid at 1.5 times that regular rate, which is a weighted average of all straight-time pay, so the differential raises the overtime rate for every overtime hour.
How do I calculate a percentage shift differential?
Multiply your base rate by the percentage. A 10% differential on $22.00 an hour is $2.20, so differential hours pay $24.20. Multiply the $2.20 by the number of differential hours to get the weekly differential pay.
Why is my overtime rate not 1.5 times my differential rate?
The minimum required overtime is based on the weighted average of all hours, not on the rate of the hours that happened to be overtime. Some contracts pay 1.5 times the shift rate for overtime worked on a differential shift, which is more generous; check your agreement.
Is weekend or holiday premium pay the same as a shift differential?
They work differently. A premium of at least 1.5 times the rate for weekend or holiday work can be left out of the regular rate and credited toward overtime, while an ordinary shift differential must be included. The holiday pay calculator handles that case.