Professional services
Fixed fee project scope overrun
Calculate remaining contribution and the extra fee needed to preserve a chosen margin after scope growth.
Your inputs
Complete the fields for your selected method. Zero means intentionally zero, not unknown. Currency selection labels amounts; it does not convert exchange rates.
How this calculation works
revised cost = original cost + extra hours × cost/hour + extra expenses; additional fee = max(0,revised cost/(1-margin)-existing fee)
Original budget already includes all baseline costs. Additional costs must be separate. This is a pricing scenario, not authorization to bill a client or interpretation of contractual scope. Use your own records for the same scope and period. Example figures are illustrative, not industry benchmarks. Results exclude income taxes and any cost you have not entered. Check the result before pricing work or committing resources.
What information do I need?
Use records for the same job, equipment or accounting period. Only the fields for your selected entry method are required. An unknown amount is not zero.
Input definitions and where to find them
- Agreed project fee before sales tax (selected currency): Use a supplier quote, invoice, payroll record or allocated cost for the exact job or period named here. Include this amount only once.
- Original full delivery cost budget (selected currency): Use a supplier quote, invoice, payroll record or allocated cost for the exact job or period named here. Include this amount only once.
- Additional person-hours now expected (person-hours): Use the matching measured quantity, time log, schedule or clearly stated estimate. Zero means intentionally none; an unknown amount is not zero.
- Loaded cost per additional person-hour (selected currency): Use a supplier quote, invoice, payroll record or allocated cost for the exact job or period named here. Include this amount only once.
- Additional non-labor expenses (selected currency): Use a supplier quote, invoice, payroll record or allocated cost for the exact job or period named here. Include this amount only once.
- Target margin on the quoted price (%): Enter a percentage from your records or an explicitly chosen scenario. No typical or recommended rate is supplied.
Use the Where to find this value controls beside the inputs for available work-it-out helpers. Estimates remain your assumptions; a helper does not verify the source figures.
Worked example
Example amounts use US dollars (USD).
Example answer: Additional fee to reach entered margin is $0.00 for the illustrative inputs below.
Example inputs
- Agreed project fee before sales tax: $5,000.00
- Original full delivery cost budget: $3,000.00
- Additional person-hours now expected: 10.00 person-hours
- Loaded cost per additional person-hour: $50.00
- Additional non-labor expenses: $100.00
- Target margin on the quoted price: 25.00 %
- Additional fee to reach entered margin
- $0.00
- Revised delivery cost
- $3,600.00
- Contribution at unchanged fee
- $1,400.00
- Margin at unchanged fee
- 28.00 %
These illustrative values are not recommended rates or industry averages. Replace every example input with your own figures.
Use the result well
Calculate remaining contribution and the extra fee needed to preserve a chosen margin after scope growth. Inputs come from your own records and stated assumptions; no rates or legal limits are looked up.
Keep inputs on the same scope and time basis. Calculations retain precision internally; displayed values generally round to two decimal places, with extra precision for very small values and whole-unit rounding where required. Economic comparisons describe your supplied assumptions and do not guarantee future results.
This tool provides business arithmetic. It does not approve engineering designs, establish legal or tax treatment, select equipment or certify safe operating conditions.