Shift Differential
Calculator
Set your base rate, add the premium each shift attracts as a percentage or a flat amount, and see the rate per shift, the total premium, and what the whole roster averages per hour.
01Your base rate
Before any shift premium
02Your shifts
A shift differential is a premium for working an unsociable shift — nights, evenings, weekends. It is normally quoted either as a percentage of your base rate or as a flat amount per hour, and which one you are on changes the answer a lot at higher base rates.
The blended rate is what the whole roster averages per hour. It is the figure to compare against a job with a higher base rate and no differential.
$40.00 of it is differential·$21.00/h blended
| Day · 24 h at $20.00/h | $480.00 | |
|---|---|---|
| Evening · 8 h at $22.00/h | $176.00 | +$16.00 |
| Night · 8 h at $23.00/h | $184.00 | +$24.00 |
| Base pay at the plain rate | $800.00 | |
| Differential premium | $40.00 | |
| Gross pay | $840 | |
| Blended rate over 40 h | $21.00/h |
This tool performs arithmetic only. It is not financial, tax, or legal advice. How these calculators are built and checked.
Percentage or flat, and why it matters
The same differential written two ways produces very different money at different base rates. Getting the form right is as important as getting the number right.
Percentage premium
A share of your base rate, so it scales with pay rises. Ten percent on $20 is $2 an hour; on $35 it is $3.50. Common in healthcare and unionised workplaces.
Flat premium
A fixed amount per hour regardless of base rate. Simple to state, but it quietly shrinks in relative terms every time your base rate goes up.
The blended rate
Total pay over total hours. This is the figure that makes a night-heavy roster comparable with a day job on a higher base rate.
A flat differential erodes
A flat differential looks identical to a percentage one on the day it is agreed and diverges every year afterwards. Two dollars an hour on a base of $20 is a 10% premium. After a few raises, on a base of $30, that same two dollars is a 6.7% premium — the inconvenience of working nights has not changed, but what you are paid for it has fallen by a third in real terms.
This is worth knowing before a negotiation rather than after. Switching the mode above, with your own base rate in the field, shows the two forms side by side; if you are on a flat differential that has not moved in several years, the gap is the argument.
Frequently asked questions
What is a shift differential?
A premium paid for working an unsociable shift — nights, evenings, weekends, or public holidays. It is added to your base hourly rate for the hours falling in that shift, and it is separate from overtime: you can be paid a differential without working a single extra hour.
How do I calculate shift differential pay?
Work out the premium per hour, add it to your base rate, then multiply by the hours in that shift. On $20 an hour with a 10% evening differential, evening hours pay $22. Do it once per shift type and add the results, which is what the table above does.
Is a differential a percentage or a flat amount?
Both exist, and which one you are on matters more than people expect. A 10% differential on $20 is $2 an hour; a flat $2 differential is the same thing at that rate but worth far less proportionally if your base rate rises to $35. Switch between the two modes above to see the gap at your own rate.
Does overtime get calculated on the differential rate?
Often it does, because many agreements base overtime on the rate actually being worked rather than the plain base rate. This calculator prices the shifts themselves — for overtime on top, take the shift rate it produces and use the time and a half calculator.
What is the blended rate for?
It is the total divided by all the hours: what your whole roster averages per hour once the premiums are in. It is the number to compare against a day-shift job with a higher base rate and no differential, because comparing base rates alone will tell you the wrong thing.
Am I entitled to a shift differential?
That depends on your contract, your employer, and sometimes your industry or jurisdiction — in many places it is entirely a matter of agreement rather than law. This calculator works out what a differential is worth once you know you have one. Check your contract or staff handbook for whether you do.
Does this show pay after deductions?
No. Every figure here is gross. What comes off depends on rules that vary by country and personal circumstance, and this site does not calculate tax of any kind.
Other calculators
- Salary Increase CalculatorWork out a new salary from a raise percentage, a flat increase, or a target figure — and compare offers side by side.
- Time to Decimal CalculatorConvert hours and minutes to decimal hours and back, with payroll rounding and a running timesheet total.
- PTO CalculatorTrack paid time off accrual, project the balance to any date, and value a payout — with caps and carryover.
- Pro Rata CalculatorScale a full-time salary to part-time hours or to part of a year, by hours or by time served.
- Time and a Half CalculatorOvertime pay at 1.5x, 2x, or a custom multiplier, including split tiers above a weekly threshold.
- Commission CalculatorCommission on sales at a flat or tiered rate, with base pay and on-target earnings.
- Billable Hours CalculatorLog tasks, round each one up to your minimum increment, and get the billable total and invoice amount.
- Nanny Pay CalculatorHourly rate, overtime, and an uplift for extra children, totalled into what is owed.
- Retro Pay CalculatorBack pay owed when a raise lands late, on an hourly rate or a salary.
- Real Estate Commission CalculatorTotal commission on a sale, split between both sides and then between each agent and their brokerage.
- Freelance Rate CalculatorWork back from target income, costs, and realistic billable days to the day rate you need to charge.
- Employee Cost CalculatorBase salary plus employer charges and benefits: the true annual cost and the multiple of salary.
- Time Card CalculatorClock in and out with unpaid breaks, night shifts across midnight, and weekly overtime on a biweekly card.
- Hours and Minutes CalculatorAdd and subtract times in h:mm, or measure the gap between two clock times including overnight.
- Salary Percentile CalculatorPlace a salary against survey breakpoints or a list you supply, with the compa-ratio. No market data assumed.
- Wage Inflation CalculatorWhat a raise was really worth once prices are taken out, and the salary needed just to stand still.
- Prevailing Wage CalculatorBase rate plus fringe from your wage determination, with benefit credits and overtime handled correctly.
- Work Schedule MakerBuild a one or two week shift rota with hours, overtime, and wage cost per person, and export it to CSV.
- Hourly to Salary CalculatorTurn an hourly rate into weekly, monthly, and annual pay — or go the other way, overtime included.