Risk Contingency Calculator
Build a risk register for a contingency reserve, and score individual risks on a probability x impact matrix.
How contingency reserve and risk exposure are calculated
The contingency reserve tool builds a full risk register — each risk scored by probability times impact (expected monetary value) — and sums those figures into a total recommended reserve, following standard PMI practice for quantifying known risks. The risk exposure score tool instead scores a single risk on a qualitative probability × impact matrix, banding the result into a recommended response (accept, transfer, mitigate, avoid) rather than a dollar figure.
The impact figures feeding into a risk register are often themselves uncertain — the PERT Estimating calculator can help produce a defensible three-point impact estimate for a given risk rather than a single guess. For evaluating a project or investment decision more broadly, including costs and benefits beyond risk alone, see the Cost-Benefit Analysis calculator.
Frequently asked questions
- How is the contingency reserve calculated?
- Each risk's expected monetary value is probability x impact; the total contingency reserve is the sum across every risk on your register. It's a standard PMI technique for known risks — unknown-unknowns typically need a separate management reserve on top.
- What do the risk matrix categories mean?
- Probability x impact is compared against the maximum possible score for your chosen scale and banded into quartiles: low (accept), medium (transfer), high (mitigate), critical (avoid) — general PMI-style guidance, not a substitute for a qualified risk assessment.
- Which scale should I use for the risk matrix?
- A 5-point scale is the most common for qualitative risk registers. Use 10 for finer-grained scoring, or 1 if you're rating probability as a 0-1 fraction directly.
- What is a contingency reserve?
- A contingency reserve is budget or time set aside specifically to cover known risks — identified items on a risk register that may or may not occur, as opposed to a general buffer for unknown, unidentified risks.
- How is the expected monetary value (EMV) of a risk calculated?
- EMV is probability multiplied by impact — a risk with a 20% chance of a $50,000 impact has an EMV of $10,000. Summing EMV across every risk on the register gives the total recommended contingency reserve.
- What is the difference between contingency reserve and management reserve?
- Contingency reserve covers known risks that have been identified and quantified on a risk register, calculated using techniques like EMV. Management reserve is a separate buffer for unknown-unknowns — risks that haven't been identified at all — and is typically controlled at a higher management level than the project team's contingency reserve.
- What risk matrix position triggers escalation?
- Risks landing in the "critical" band (high probability and high impact combined) typically warrant escalation and an avoidance strategy, while "high" band risks usually call for active mitigation. Lower bands (low, medium) are more often accepted or transferred rather than escalated — exact thresholds should match your organization's own risk tolerance.
- How do I determine the right contingency percentage?
- Summing the EMV of every identified risk and dividing by the total project budget gives a data-driven contingency percentage, rather than relying on a generic industry rule of thumb (commonly cited figures range from 5–20% depending on project type and maturity) — building a specific risk register produces a more defensible number for your particular project.