Shift Differential Calculator
A shift differential is extra pay for less popular shifts — nights, evenings, weekends. A 10% differential on $20 an hour pays $22 an hour for those hours. The calculator also works out overtime correctly, because the differential must be included in the regular rate.
- Differential rate = base rate × (1 + %) or base + flat amount.
- 10% on $20/h = $22/h; $2 flat on $20/h is the same.
- Differentials are not required by US federal law.
- They must be included in the overtime regular rate.
How shift differential pay works
Employers add a premium to hours worked at times that are harder to staff. The two common forms:
- Percentage: a share of the base rate, e.g. 10% for nights. It scales with seniority and pay raises.
- Flat amount: a fixed amount per hour, e.g. $1.50 for evenings. It is simpler and the same for everyone.
Weekly pay = base hours × base rate + differential hours × differential rate, plus overtime if the week goes over 40 hours.
How to use the Shift Differential calculator
Fill in the fields above and press Calculate. Results appear straight away, in your browser — nothing is sent or stored.
- Base hourly rate — starts at 20; replace it with your own figure.
- Differential type — choose from: Percentage of base, Flat $ per hour.
- Differential — starts at 10; replace it with your own figure.
- Hours at the differential rate — starts at 24; replace it with your own figure.
- Hours at the base rate — starts at 20; replace it with your own figure.
- Pay overtime over 40 hours (US federal rule) — tick or untick as needed.
Change any value and press Calculate again to compare scenarios. All figures are estimates for planning; check them against your own policy, contract and local rules before using them for payroll.
Shift differential chart
Differential hourly rates for common base wages.
| Base rate | +5% | +10% | +15% | +$1/h | +$2/h |
|---|---|---|---|---|---|
| $15.00 | $15.75 | $16.50 | $17.25 | $16.00 | $17.00 |
| $18.00 | $18.90 | $19.80 | $20.70 | $19.00 | $20.00 |
| $20.00 | $21.00 | $22.00 | $23.00 | $21.00 | $22.00 |
| $22.00 | $23.10 | $24.20 | $25.30 | $23.00 | $24.00 |
| $25.00 | $26.25 | $27.50 | $28.75 | $26.00 | $27.00 |
| $30.00 | $31.50 | $33.00 | $34.50 | $31.00 | $32.00 |
| $35.00 | $36.75 | $38.50 | $40.25 | $36.00 | $37.00 |
Shift differential: quick answers
What is a 5% differential on $20 an hour?
The differential rate is $21.00 an hour ($1.00 extra per hour).
What is a 10% differential on $18 an hour?
The differential rate is $19.80 an hour ($1.80 extra per hour).
What is a 10% differential on $20 an hour?
The differential rate is $22.00 an hour ($2.00 extra per hour).
What is a 10% differential on $25 an hour?
The differential rate is $27.50 an hour ($2.50 extra per hour).
What is a 15% differential on $20 an hour?
The differential rate is $23.00 an hour ($3.00 extra per hour).
What is a 15% differential on $30 an hour?
The differential rate is $34.50 an hour ($4.50 extra per hour).
What is a 20% differential on $22 an hour?
The differential rate is $26.40 an hour ($4.40 extra per hour).
What is a $1 differential on $20 an hour?
The differential rate is $21.00 an hour ($1.00 extra per hour).
What is a $2 differential on $25 an hour?
The differential rate is $27.00 an hour ($2.00 extra per hour).
What is a $3 differential on $18 an hour?
The differential rate is $21.00 an hour ($3.00 extra per hour).
Shift differentials and overtime
Under the FLSA, a shift differential is part of the employee’s regular rate. When the week includes overtime, the overtime premium is calculated on the weighted average of all hourly earnings, not the base rate.
Example: base $20, 10% night differential, 24 night hours and 20 day hours (44 total). Straight-time pay = 20 × $20 + 24 × $22 = $928. Regular rate = $928 ÷ 44 = $21.09. Overtime premium = 0.5 × $21.09 × 4 = $42.18. Total pay = $970.18. Paying the premium on the $20 base instead ($40) would underpay the employee every overtime week.
If the overtime hours themselves fall on night shifts, some employers pay 1.5 × the differential rate for those hours — that is at least as much as the law requires. The overtime calculator handles bonuses the same way.
Worked examples
Real-world scenarios, worked through step by step.
Night nurse, percentage differential
$38 base, 12% nights, 36 night hours: 36 × $42.56 = $1,532.16 for the week, of which $164.16 is differential pay.
Warehouse evening shift, flat premium
$19 base + $1.50 evenings, 40 evening hours: 40 × $20.50 = $820.
Mixed week with overtime
$20 base, 10%, 24 night + 20 day hours: total $970.18 including a $42.18 overtime premium on the $21.09 regular rate.
Weekend premium
$16 base, +$2 Saturday and Sunday, 16 weekend hours and 24 weekday hours: 24 × $16 + 16 × $18 = $672.
Typical differential amounts
There is no legal standard amount. Differentials are set by employer policy, union agreements or, for public employers, pay rules. In practice:
- Evening shifts often carry a smaller premium than overnight shifts.
- Overnight (“graveyard”) shifts typically carry the largest premium.
- Weekend and holiday premiums are common in healthcare, manufacturing and security.
- Hazard or on-call premiums are separate from shift differentials but also count toward the regular rate.
Healthcare, call centers, logistics and manufacturing use differentials most — see how StaffTiming handles healthcare shifts and call center rosters.
Which hours qualify?
A clear policy prevents disputes. Define:
- The qualifying window (e.g. 11 PM–7 AM, or any hours after 6 PM).
- Whether the whole shift qualifies if most of it falls in the window, or only the hours inside it.
- Whether paid time off and holidays include the differential.
- How differential hours interact with overtime.
Shifts that cross midnight are where manual calculation goes wrong — record the actual clock times and let the system split them. The time duration calculator helps check a single shift.
Recording differential hours accurately
Differential pay depends on knowing exactly when each hour was worked, not just how many. Paper timesheets that record only daily totals cannot support it. A time tracking system with clock-in times splits day and night hours automatically and feeds the right rate into payroll.
Budgeting for a 24/7 roster
For employers, the cost of a differential is easy to underestimate because it compounds: it applies to every qualifying hour, it raises the overtime rate, and it is often included in paid holidays. A simple way to budget it:
- Count the qualifying hours per week across the roster (e.g. 3 night positions × 56 hours = 168 hours).
- Multiply by the per-hour premium (e.g. 10% of $22 = $2.20) → $369.60 a week.
- Add the overtime effect: overtime on those positions is paid on the higher regular rate.
- Multiply by 52 for the annual cost — about $19,200 in this example before overtime.
Compare that with the cost of vacancies and turnover on hard-to-fill shifts; the employee turnover cost calculator and the employee cost calculator give the other side of the equation. A good differential often pays for itself by keeping night shifts staffed.
Common payroll errors with differentials
- Paying overtime on the base rate instead of the weighted regular rate.
- Applying the differential to the whole shift when the policy covers only hours inside the window (or vice versa).
- Forgetting the differential on holiday or call-in hours where the policy includes it.
- Recording only daily totals, so nobody can tell which hours were nights.
Do it in Excel or Google Sheets
Put the base rate in B2, the differential percentage in C2 (e.g. 10%), differential hours in D2 and base hours in E2.
- Differential rate
=B2*(1+C2) - Straight-time pay
=B2*E2+B2*(1+C2)*D2 - Regular rate
=(B2*E2+B2*(1+C2)*D2)/(D2+E2) - Overtime premium over 40 h
=0.5*((B2*E2+B2*(1+C2)*D2)/(D2+E2))*MAX(0,D2+E2-40)
For a flat differential replace B2*(1+C2) with B2+C2 and enter the dollar amount in C2.
Who uses the Shift Differential calculator — and why
- Hospitals and care homes paying night and weekend nurses.
- Call centers running 24/7 rosters.
- Manufacturing and warehouses with second and third shifts.
- Security and facilities teams.
- Payroll teams checking that overtime includes the differential.
- Employees comparing day and night shift pay.
How we calculate
- Differential rate = base × (1 + %) or base + flat amount.
- Regular rate = (base hours × base + differential hours × differential rate) ÷ total hours; overtime premium = 0.5 × regular rate × hours over 40.
- Shift premiums are part of the regular rate under 29 CFR 778.207(b).
- All calculations run in your browser; nothing you type is sent to StaffTiming or stored.
Formulas checked against the sources above. Last reviewed: October 2026. This tool gives estimates for planning, not legal, tax or payroll advice.
Key terms explained
- Shift differential
- Extra pay for working a less desirable shift.
- Graveyard shift
- An overnight shift, typically starting around 11 PM.
- Swing shift
- An evening shift between day and night shifts.
- Flat differential
- A fixed amount added per hour.
- Percentage differential
- A premium calculated as a percentage of the base rate.
- Regular rate
- Total straight-time pay ÷ hours worked, used for overtime.
- Weighted average rate
- The regular rate when an employee earns different rates in one week.
- Premium pay
- Any pay above the base rate for specific hours or conditions.
Frequently asked questions
How do you calculate a 10% shift differential?
Multiply the base rate by 1.10. At $20 an hour, the night rate is $22.
Is shift differential required by law?
Not under US federal law. It is set by company policy, contracts or union agreements.
Is shift differential included in overtime?
Yes. Under the FLSA, differentials are part of the regular rate used to calculate overtime.
What is a typical night shift differential?
It varies by industry and region. Overnight shifts usually carry a larger premium than evening shifts.
Is a flat or percentage differential better?
Percentages grow with pay raises; flat amounts are simpler and equal for everyone. Both are common.
Does PTO include shift differential?
Only if your policy says so. It is an employer choice.
Do weekend premiums count toward the regular rate?
Generally yes, unless they qualify as specific excludable premium pay. Check the details before excluding them.
How do I calculate pay when a shift crosses midnight?
Split the shift into the hours inside and outside the differential window, and pay each at its rate.
What is a $2 shift differential?
$2 extra for every qualifying hour. On a $20 base the qualifying rate is $22.
Can different shifts have different differentials?
Yes. Many employers pay a smaller evening premium and a larger overnight premium.
Do salaried employees get shift differentials?
They can, if the employer’s policy provides it. For non-exempt salaried staff, the differential also feeds into overtime.
How is a holiday differential different?
A holiday premium is extra pay for working on a holiday. It is a separate policy, though it may stack with a night differential.
Is shift differential taxed differently?
No. It is ordinary wages and is taxed like the rest of your pay.
How do I calculate a 15% night differential?
Multiply the base rate by 1.15. At $24 an hour, the night rate is $27.60, an extra $3.60 per night hour.
How much extra is a 10% differential over a year?
At $20 an hour and 20 night hours a week, the extra pay is $2 × 20 × 52 = $2,080 a year.
Does a shift differential count for vacation pay?
Only if the employer’s policy includes it. Many pay vacation at the base rate.
Is a shift differential part of the regular rate for overtime?
Yes. Under the FLSA, shift premiums are included in the regular rate, so they raise the overtime rate in weeks with overtime.
Can an employer stop paying a shift differential?
Generally yes for future hours, with notice, unless a contract or union agreement requires it. Hours already worked must be paid at the promised rate.
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