Back Pay Calculator

For a flat rate gap, the formula is exactly what the calculator shows:

(correct hourly rate − paid hourly rate) × hours per week affected × weeks affected. That is the back pay you receive. Separately, 12% superannuation is owed on the part of it that counts as qualifying earnings — ordinary hours, casual loading and penalty rates for ordinary hours, but not overtime. It is paid by your employer into your super fund, not to you, so the calculator keeps it out of the headline figure. The super line applies 12% to the whole shortfall, so it is an upper bound if any of the affected hours were overtime. Courts and the Fair Work Ombudsman can add interest on top, and the calculation runs per pay period at the rate that applied at the time, so a gap that straddles a 1 July increase is calculated in two segments.

What a flat formula genuinely cannot price:

• Missed penalty rates — if your Sundays were paid at the weekday rate, the gap only applies to Sunday hours, at the penalty-rate difference. That needs your actual rosters.
• Missing allowances — sleepovers ($62.87/night), broken shifts ($21.81), vehicle kilometres ($1.05/km in the temporary window from the first full pay period on or after 1 September 2026 to 28 February 2027; $1.01/km otherwise) are flat amounts per event, so the back pay is the count of events, not an hourly gap.
• Overtime and minimum engagements — both depend on when and how long each shift ran.

That per-shift arithmetic is exactly what underpayment usually looks like in care work — which is why the wages estimate above is a floor, not a ceiling.

The calculator is only as good as the "should have been paid" number. That rate comes from your award and classification, not from job ads or colleagues:

• Disability, community and home-care workers (SCHADS Award): our current rate tables list every level and pay point at the 1 July 2026 rates, and the levels guide explains which classification your duties match.
• Everyone else: the Fair Work Ombudsman's P.A.C.T. calculator covers every modern award and is the reference figure regulators themselves use.
• Casuals: remember the 25% loading belongs in your correct rate.

An estimate opens the conversation; payslips settle it. If you work under the SCHADS Award, upload a payslip to our free payslip check and it compares every line — base rate, weekend rates, sleepover and broken-shift allowances, kilometres — against the current Fair Work minimums, and tells you with dollar figures which lines are below the minimum. That's the specific, dated evidence that turns "I think I'm underpaid" into a question your employer has to answer properly — and if it goes further, the Fair Work Ombudsman takes complaints free of charge, with claims reaching back up to 6 years.