Act on the result
Choose the model whose risk allocation matches the scope and contract.
Educational only: Business decision support, not accounting, tax or legal advice.
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Update policy: Reviewed when formulas or official dependencies change.
Scope: Market-neutral small-business planning using your own assumptions.
What this planner helps you decide
Best for
Service owners choosing between fixed-fee and hourly project billing.
Outputs
Break-even hours, expected fixed/hourly contribution and best, base and worst case outcomes.
Start here
Enter ordered best, base and worst delivery hours, probabilities, both prices, cost and the fixed-fee scope buffer.
Use a different tool when: Do not use this to measure unrecovered scope change; use Scope Creep Impact Planner for that decision. Use this tool to compare fixed-fee and hourly economics.
Quote & capacity
Fixed Price vs Hourly: break-even hours
Break-even hours, expected fixed/hourly contribution and best, base and worst case outcomes.
Amounts use the same currency as your inputs. No currency conversion is performed.
Fixed Price vs Hourly
Compare fixed and hourly contribution across best, base and worst delivery cases. The fixed-fee scope buffer is a revenue mark-up: fixed fee ร (1 + buffer rate).
Your numbers stay in this browser
Client rate per hour.
Fixed-fee option.
Internal hourly cost.
Revenue mark-up for uncertainty, applied as fixed fee ร (1 + buffer rate).
Upside delivery case.
Probability assigned to the upside case.
Expected delivery case.
Probability assigned to the base case.
Downside delivery case.
Probability assigned to the downside case.
Decision result
Every result is derived by the registered service and project engine.
PDF and CSV exports stay on this device. Clean page links contain no inputs.
- Protected Fixed Revenue
- 7,700.00/project
- Break Even Hours
- 51.33 hours/project
- Expected Fixed Contribution
- 4,693.75/project
- Expected Hourly Contribution
- 3,931.25/project
- Fixed-price contribution difference
- 762.50/project
- Best Fixed Contribution
- 5,425.00/project
- Best Hourly Contribution
- 2,975.00/project
- Base Fixed Contribution
- 4,775.00/project
- Base Hourly Contribution
- 3,825.00/project
- Worst Fixed Contribution
- 3,800.00/project
- Worst Hourly Contribution
- 5,100.00/project
Scenario comparison
Each row names the assumption axis changed from the baseline.
ScenarioResultDifference
Current scenario762.50/projectBaseline
Lower Worst-case hours875.00/project+112.50/project (+14.8%)
Higher Worst-case hours650.00/projectโ112.50/project (โ14.8%)
Save these results, change an input, then compare the updated figures with this baseline.
The baseline is temporary in this tab and is not added to shared scenario links or generated reports.
Calculation details
View calculation detailsView the formulas and inputs used for these results.
Fixed-price contribution difference
Contribution Difference
fixed-price contribution โ hourly contribution762.50/projectResult762.50/project
Reports/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Contribution DifferenceHourly Rate
- 150
- Contribution DifferenceFixed Fee
- 7,000
- Contribution DifferenceDelivery Cost Per Hour
- 65
- Contribution DifferenceScope Buffer Rate
- 0.1
- Contribution DifferenceBest Case Hours
- 35
- Contribution DifferenceBest Case Probability
- 0.25
- Contribution DifferenceBase Case Hours
- 45
- Contribution DifferenceBase Case Probability
- 0.5
- Contribution DifferenceWorst Case Hours
- 60
- Contribution DifferenceWorst Case Probability
- 0.25
Protected Fixed Revenue
Protected Fixed Revenue
fixed fee ร (1 + scope buffer)7,700/projectResult7,700.00/project
Reports/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Protected Fixed RevenueHourly Rate
- 150
- Protected Fixed RevenueFixed Fee
- 7,000
- Protected Fixed RevenueDelivery Cost Per Hour
- 65
- Protected Fixed RevenueScope Buffer Rate
- 0.1
- Protected Fixed RevenueBest Case Hours
- 35
- Protected Fixed RevenueBest Case Probability
- 0.25
- Protected Fixed RevenueBase Case Hours
- 45
- Protected Fixed RevenueBase Case Probability
- 0.5
- Protected Fixed RevenueWorst Case Hours
- 60
- Protected Fixed RevenueWorst Case Probability
- 0.25
Break Even Hours
Break Even Hours
protected fixed revenue รท hourly rate51.33 hours/projectResult51.33 hours/project
Reports hours/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Break Even HoursHourly Rate
- 150
- Break Even HoursFixed Fee
- 7,000
- Break Even HoursDelivery Cost Per Hour
- 65
- Break Even HoursScope Buffer Rate
- 0.1
- Break Even HoursBest Case Hours
- 35
- Break Even HoursBest Case Probability
- 0.25
- Break Even HoursBase Case Hours
- 45
- Break Even HoursBase Case Probability
- 0.5
- Break Even HoursWorst Case Hours
- 60
- Break Even HoursWorst Case Probability
- 0.25
Expected Fixed Contribution
Expected Fixed Contribution
ฮฃ(fixed case contribution ร probability)4,693.75/projectResult4,693.75/project
Reports/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Expected Fixed ContributionHourly Rate
- 150
- Expected Fixed ContributionFixed Fee
- 7,000
- Expected Fixed ContributionDelivery Cost Per Hour
- 65
- Expected Fixed ContributionScope Buffer Rate
- 0.1
- Expected Fixed ContributionBest Case Hours
- 35
- Expected Fixed ContributionBest Case Probability
- 0.25
- Expected Fixed ContributionBase Case Hours
- 45
- Expected Fixed ContributionBase Case Probability
- 0.5
- Expected Fixed ContributionWorst Case Hours
- 60
- Expected Fixed ContributionWorst Case Probability
- 0.25
Expected Hourly Contribution
Expected Hourly Contribution
ฮฃ(hourly case contribution ร probability)3,931.25/projectResult3,931.25/project
Reports/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Expected Hourly ContributionHourly Rate
- 150
- Expected Hourly ContributionFixed Fee
- 7,000
- Expected Hourly ContributionDelivery Cost Per Hour
- 65
- Expected Hourly ContributionScope Buffer Rate
- 0.1
- Expected Hourly ContributionBest Case Hours
- 35
- Expected Hourly ContributionBest Case Probability
- 0.25
- Expected Hourly ContributionBase Case Hours
- 45
- Expected Hourly ContributionBase Case Probability
- 0.5
- Expected Hourly ContributionWorst Case Hours
- 60
- Expected Hourly ContributionWorst Case Probability
- 0.25
Best Fixed Contribution
Best Fixed Contribution
protected fixed revenue โ best hours ร delivery cost5,425/projectResult5,425.00/project
Reports/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Best Fixed ContributionHourly Rate
- 150
- Best Fixed ContributionFixed Fee
- 7,000
- Best Fixed ContributionDelivery Cost Per Hour
- 65
- Best Fixed ContributionScope Buffer Rate
- 0.1
- Best Fixed ContributionBest Case Hours
- 35
- Best Fixed ContributionBest Case Probability
- 0.25
- Best Fixed ContributionBase Case Hours
- 45
- Best Fixed ContributionBase Case Probability
- 0.5
- Best Fixed ContributionWorst Case Hours
- 60
- Best Fixed ContributionWorst Case Probability
- 0.25
Best Hourly Contribution
Best Hourly Contribution
best hours ร (hourly rate โ delivery cost)2,975/projectResult2,975.00/project
Reports/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Best Hourly ContributionHourly Rate
- 150
- Best Hourly ContributionFixed Fee
- 7,000
- Best Hourly ContributionDelivery Cost Per Hour
- 65
- Best Hourly ContributionScope Buffer Rate
- 0.1
- Best Hourly ContributionBest Case Hours
- 35
- Best Hourly ContributionBest Case Probability
- 0.25
- Best Hourly ContributionBase Case Hours
- 45
- Best Hourly ContributionBase Case Probability
- 0.5
- Best Hourly ContributionWorst Case Hours
- 60
- Best Hourly ContributionWorst Case Probability
- 0.25
Base Fixed Contribution
Base Fixed Contribution
protected fixed revenue โ base hours ร delivery cost4,775/projectResult4,775.00/project
Reports/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Base Fixed ContributionHourly Rate
- 150
- Base Fixed ContributionFixed Fee
- 7,000
- Base Fixed ContributionDelivery Cost Per Hour
- 65
- Base Fixed ContributionScope Buffer Rate
- 0.1
- Base Fixed ContributionBest Case Hours
- 35
- Base Fixed ContributionBest Case Probability
- 0.25
- Base Fixed ContributionBase Case Hours
- 45
- Base Fixed ContributionBase Case Probability
- 0.5
- Base Fixed ContributionWorst Case Hours
- 60
- Base Fixed ContributionWorst Case Probability
- 0.25
Base Hourly Contribution
Base Hourly Contribution
base hours ร (hourly rate โ delivery cost)3,825/projectResult3,825.00/project
Reports/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Base Hourly ContributionHourly Rate
- 150
- Base Hourly ContributionFixed Fee
- 7,000
- Base Hourly ContributionDelivery Cost Per Hour
- 65
- Base Hourly ContributionScope Buffer Rate
- 0.1
- Base Hourly ContributionBest Case Hours
- 35
- Base Hourly ContributionBest Case Probability
- 0.25
- Base Hourly ContributionBase Case Hours
- 45
- Base Hourly ContributionBase Case Probability
- 0.5
- Base Hourly ContributionWorst Case Hours
- 60
- Base Hourly ContributionWorst Case Probability
- 0.25
Worst Fixed Contribution
Worst Fixed Contribution
protected fixed revenue โ worst hours ร delivery cost3,800/projectResult3,800.00/project
Reports/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Worst Fixed ContributionHourly Rate
- 150
- Worst Fixed ContributionFixed Fee
- 7,000
- Worst Fixed ContributionDelivery Cost Per Hour
- 65
- Worst Fixed ContributionScope Buffer Rate
- 0.1
- Worst Fixed ContributionBest Case Hours
- 35
- Worst Fixed ContributionBest Case Probability
- 0.25
- Worst Fixed ContributionBase Case Hours
- 45
- Worst Fixed ContributionBase Case Probability
- 0.5
- Worst Fixed ContributionWorst Case Hours
- 60
- Worst Fixed ContributionWorst Case Probability
- 0.25
Worst Hourly Contribution
Worst Hourly Contribution
worst hours ร (hourly rate โ delivery cost)5,100/projectResult5,100.00/project
Reports/project from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Fixed Price vs Hourly Planner formulas โInputs used by these formula steps
- Worst Hourly ContributionHourly Rate
- 150
- Worst Hourly ContributionFixed Fee
- 7,000
- Worst Hourly ContributionDelivery Cost Per Hour
- 65
- Worst Hourly ContributionScope Buffer Rate
- 0.1
- Worst Hourly ContributionBest Case Hours
- 35
- Worst Hourly ContributionBest Case Probability
- 0.25
- Worst Hourly ContributionBase Case Hours
- 45
- Worst Hourly ContributionBase Case Probability
- 0.5
- Worst Hourly ContributionWorst Case Hours
- 60
- Worst Hourly ContributionWorst Case Probability
- 0.25
Inputs used
- Hourly billing rate
- 150
- Fixed project fee
- 7,000
- Delivery cost per hour
- 65
- Fixed-fee scope buffer
- 0.1
- Best-case hours
- 35
- Best-case probability
- 0.25
- Base-case hours
- 45
- Base-case probability
- 0.5
- Worst-case hours
- 60
- Worst-case probability
- 0.25
Open this calculator with preset values
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| Parameter | Meaning | Unit | Allowed values | Presence | Default |
|---|---|---|---|---|---|
| baseCaseHours | Expected delivery case. | hours/project | 0 to 10000000 | Required | 45 |
| baseCaseProbability | Probability assigned to the base case. | decimal probability | 0 to 0.99 | Required | 0.5 |
| bestCaseHours | Upside delivery case. | hours/project | 0 to 10000000 | Required | 35 |
| bestCaseProbability | Probability assigned to the upside case. | decimal probability | 0 to 0.99 | Required | 0.25 |
| deliveryCostPerHour | Internal hourly cost. | currency units/hour | 0 to 10000000 | Required | 65 |
| fixedFee | Fixed-fee option. | currency units/project | 0 to 10000000 | Required | 7000 |
| hourlyRate | Client rate per hour. | currency units/hour | 0 to 10000000 | Required | 150 |
| scopeBufferRate | Revenue mark-up for uncertainty, applied as fixed fee ร (1 + buffer rate). | proportion of delivery cost added as scope buffer | 0 to 0.99 | Required | 0.1 |
| worstCaseHours | Downside delivery case. | hours/project | 0 to 10000000 | Required | 60 |
| worstCaseProbability | Probability assigned to the downside case. | decimal probability | 0 to 0.99 | Required | 0.25 |
Fixed Price vs Hourly: break-even hours
The fixed price vs hourly result uses only the entered commercial assumptions.
Formula summary
- Primary formula
- expected contribution = ฮฃ(case contribution ร case probability)
Data used here
- The estimate uses your inputs and the general business formula documented in the methodology.
Decision checks
Stress-test the decision
Increase worst-case hours and probability before accepting a fixed fee.
When this estimate can be misleading
- Results depend on the accuracy and consistent basis of user-entered assumptions.
- The planner does not forecast demand, delivery performance or contract outcomes.
- Use the result as educational business decision support, not accounting, tax or legal advice.
- The fixed price vs hourly result uses only the entered commercial assumptions.
Educational estimate, not advice. See all assumptions & limitations โ
Related reading
Guides to interpret the decision and its assumptions.
- Hourly vs Project vs Retainer Pricing
Compare how hourly, fixed-project and retainer models allocate duration, scope and reserved-capacity risk.
Read guide
Frequently asked questions
How do I compare fixed-fee and hourly economics?
Choose the model whose risk allocation matches the scope and contract.
Which planning assumptions should I stress-test?
Compare a plausible alternative scenario and verify the decision-critical assumption that changes the plan most.