How to Calculate Shift Differential Pay

Step 1: Turn the differential into dollars per hour

A flat differential is already in dollars per hour. A percentage differential needs one multiplication: base rate × percentage ÷ 100.

• 10% of a $20.00 base rate is $2.00 an hour.
• 8% of a $26.50 base rate is $2.12 an hour.
• 12% of a $17.35 base rate is $2.082 an hour — a fraction of a cent, which matters later.

Step 2: Multiply by the hours that earn it

Only the hours your employer pays the differential on count. If you worked 40 hours but 32 of them were on the evening shift, use 32. With the 8% differential on $26.50: $2.12 × 32 hours = $67.84 of differential pay.

Step 3: Add it to your base pay

1. Base pay for those hours: $26.50 × 32 = $848.00.
2. Differential pay: $67.84.
3. Total for those hours: $848.00 + $67.84 = $915.84.
4. Effective hourly rate on those hours: $26.50 + $2.12 = $28.62.

More worked examples

When the rate has a fraction of a cent

A percentage often gives a rate that isn’t a whole number of cents. Payroll systems handle it in different ways, and the choice can move the result by a few cents. Using the exact $2.082 for 40 hours gives $83.28. Rounding the rate to $2.08 first gives $83.20 — 8 cents less. The Shift Differential Calculator keeps the exact rate and rounds only the pay, and it shows the exact rate in its working so you can compare.

Checking the result against a pay stub

• Look for a separate line such as “shift diff,” “evening premium,” or “night differential,” and compare its hours with the hours you entered.
• If the stub’s differential hours are lower, your employer may count only hours inside a set window rather than the whole shift.
• Some stubs fold part of a premium into other lines, such as overtime. If the totals don’t match, compare each line’s hours and rate rather than the grand total.