Project contingency calculator
Calculate a project reserve as a percentage of the base estimate, then see the total.
Try a worked example
Try a worked example
Calculate a project reserve as a percentage of the base estimate, then see the total.
Check the units and options, then use the tool’s calculation button. The example is fictitious; replace its values for your own calculation.
Illustration only. Supply the applicable rates and assumptions yourself; this is not financial, tax or legal advice.
Example input
- Base estimate before reserve
- 5000
- Reserve rate (% of base)
- 10
- Currency
- EUR €
Expected output
Base estimate before reserve: €5,000.00 Contingency reserve: €500.00 Estimated total including reserve: €5,500.00
Calculates the reserve as a percentage of the base estimate and adds it to that base.
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Method and limits
The result depends on the values entered and the method shown. Check the assumptions, rates, or rules that apply to your situation before using it. Illustrative result only. Verify the rules and assumptions that apply to your work.
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Quick answer
Calculates the reserve as a percentage of the base estimate and adds it to that base.
The page code is downloaded when you open it; values are handled in your browser.
Limits of the result
The result depends on the values entered and the method shown. Check the assumptions, rates, or rules that apply to your situation before using it. Illustrative result only. Verify the rules and assumptions that apply to your work.
Frequently asked questions
What does the calculation include?
Reserve = base estimate × entered percentage. With the prefilled example, 5,000 × 10% = 500 reserve and 5,500 total. The percentage applies to the base only, not to the reserve. The tool does not calculate VAT or taxes, analyse risks, or determine which reserve rate is appropriate. Use the same tax basis as your estimate.
Which values should I enter?
Calculate a project reserve as a percentage of the base estimate, then see the total. Use consistent amounts, units, and time periods.
Is the result definitive?
No. Check the assumptions and rules that apply to your situation; this is an illustrative calculation, not professional advice.
Sources and references
These references describe the cited context and rules; some apply only in the jurisdiction named in their title. They do not validate this illustrative calculation.