Calculate a risk severity score from probability and impact ratings, with classification and interpretation.
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Parameters
Result
Interpretation
Risk is moderate. Plan mitigation steps and review regularly.
Statistics
A severity calculator computes a risk severity score by multiplying probability and impact ratings on a 1–10 scale. The resulting score (1–100) is classified as Low, Medium, High, or Critical, providing a quick risk assessment for project management and safety analysis.
Severity = Probability × Impact. Both factors are rated on a 1–10 scale, producing a score from 1 to 100. The score maps to four levels: Low (1–20), Medium (21–50), High (51–80), and Critical (81–100).
This approach is widely used in risk matrices for project management, safety engineering, and quality assurance.
Severity = Probability × Impact
Risk severity score formula. This is the specific relationship the calculator applies when building the result.
A worked example helps translate the severity calculator maths into a realistic scenario so the user can compare the headline result with a concrete set of inputs.
That matters because a result is easier to trust when the page shows how the same logic behaves in a practical case instead of leaving the formula abstract.
Use the severity calculator output as a planning aid, then compare it with the assumptions, units, and caveats shown elsewhere on the page before acting on the number alone.
That extra interpretation step matters because a calculator can simplify the arithmetic but still cannot replace real-world context such as local rules, contract terms, or individual circumstances.
Frequently asked questions
Both use a 1–10 scale where 1 is lowest (very unlikely / negligible impact) and 10 is highest (almost certain / catastrophic impact).
The standard thresholds (Low ≤20, Medium ≤50, High ≤80, Critical ≤100) are widely used, but organizations may adjust them based on their risk tolerance.
The safest manual check is to follow the same formula or rule one step at a time and compare that working with the calculator output. That catches sign errors, bracket mistakes, and input-order mixups without requiring any extra method beyond the underlying maths itself.
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