Workshop Hub

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Job profit calculator for mechanics

Before you send the invoice, check what the job actually made. Enter labour hours, your charge-out rate, parts sell and cost, and see profit and margin ex GST. All figures in AUD. Nothing you type is stored.

Labour

Hours on the job and your rates.

Wage plus super, workers’ comp and leave loading.

Parts and other

Sell and cost, ex GST.

Sublet, consumables you do not mark up, tow fees you absorb.

Job profit

Profit on this job (ex GST)

$310

Margin 54.6%. Customer total about $624 inc GST.

Labour sell (ex GST)
$387.50
Labour cost (ex GST)
$162.50
Labour profit
$225.00
Parts profit
$85.00
Revenue (ex GST)
$567.50
Approx. GST
$56.75

Estimates only, not a guarantee. Results come from the numbers and assumptions you set, not from measured customer data, so your shop may do better or worse. All figures are AUD excluding GST unless stated. Nothing you enter is stored or sent anywhere.

Workshop Hub flags missing labour and consumables before the invoice goes out, and keeps parts cost on the job card. Try the live demo · See features.

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How job profit is worked out

  1. Labour sell (ex GST) = billable hours × labour rate.
  2. Labour cost (ex GST) = billable hours × technician cost rate (wage + on-costs per hour).
  3. Parts profit (ex GST) = parts sell − parts cost.
  4. Job profit (ex GST) = labour sell − labour cost + parts profit − other costs.
  5. Margin % = job profit ÷ (labour sell + parts sell) × 100.
  6. GST on the customer invoice ≈ (labour sell + parts sell) × 10% when you are registered.

About the example numbers

  • Starting numbers are an example job, not a benchmark. Replace them with the job in front of you.
  • Technician cost rate should include super, workers’ comp and leave loading — not just base wage.
  • Parts cost is what you paid the supplier, ex GST.

Ways to protect job profit

  • Flag unbilled diagnostic time before the invoice goes out.
  • Apply a consistent parts markup and check supplier invoices match what you charged.
  • Watch comebacks — free rework wipes the margin on the original job.

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Questions about this calculator

Should I include GST in these figures?
Enter labour and parts ex GST. GST is collected for the ATO and is not profit. The calculator shows an approximate GST line for the customer total.
What margin should a workshop aim for?
It varies by work type and location. Many shops watch labour efficiency and parts markup separately, then look at overall job margin. Use your accountant’s targets.
Does this store my numbers?
No. Everything runs in your browser.