Information Security Risk Calculator

Risk Input Form

Use 1 to 5 scales for qualitative ratings. Higher numbers indicate greater exposure or impact.

Asset Name

Asset Value ($)

Exposure Factor (%)

Incident Frequency (per year)

Threat Likelihood (1-5)

Vulnerability Severity (1-5)

Data Sensitivity (1-5)

Service Criticality (1-5)

Reputation Impact (1-5)

Compliance Impact (1-5)

Control Effectiveness (%)

Plotly Risk Graph

Example Data Table

Asset	Asset Value	Threat	Vulnerability	Control %	Residual Score	Priority
Customer Database	$500,000	4	4	30%	53.20	Priority Action
Public Web Server	$120,000	3	3	60%	14.40	Monitor
Finance ERP	$900,000	5	4	45%	49.50	Priority Action

Formula Used

Impact Score
Impact Score = Average(Data Sensitivity, Service Criticality, Reputation Impact, Compliance Impact) ÷ 5 × 100

Likelihood Score
Likelihood Score = Average(Threat Likelihood, Vulnerability Severity) ÷ 5 × 100

Inherent Risk Score
Inherent Risk Score = Impact Score × Likelihood Factor

Residual Risk Score
Residual Risk Score = Inherent Risk Score × (1 − Control Effectiveness ÷ 100)

SLE, ARO, and ALE
SLE = Asset Value × Exposure Factor
ARO = Incident Frequency × Likelihood Factor
ALE = SLE × ARO

This approach combines qualitative security scoring with financial loss estimation, which makes prioritization easier for governance, operations, and budgeting decisions.

How to Use This Calculator

Enter the asset name and estimated monetary value.
Set the expected exposure factor as a percentage loss.
Provide annual incident frequency for the risk scenario.
Rate threat likelihood and vulnerability severity from 1 to 5.
Rate business impact fields from 1 to 5.
Enter current control effectiveness as a percentage.
Click the calculate button to see scores and loss estimates.
Review the chart, summary table, and export options.

Frequently Asked Questions

1. What does residual risk mean?

Residual risk is the remaining risk after existing security controls are considered. It helps teams understand whether current safeguards lower exposure enough or whether more treatment is still needed.

2. Why use both risk scores and ALE?

A normalized score supports prioritization across many assets. ALE adds financial context, helping decision makers compare remediation cost against expected annual loss.

3. What is a good control effectiveness value?

There is no universal number. Higher effectiveness suggests stronger mitigation, but the value should come from audits, testing, monitoring outcomes, and real control performance evidence.

4. Can this calculator replace a full risk assessment?

No. It is a practical screening and prioritization tool. Formal assessments still need scope review, asset inventories, threat intelligence, stakeholder input, and documented risk acceptance.

5. How should I set the 1 to 5 ratings?

Define scoring criteria internally. For example, 1 can mean minimal impact or rare likelihood, while 5 can mean severe impact or very probable occurrence.

6. What does exposure factor represent?

Exposure factor estimates the percentage of asset value lost if the event happens once. It reflects direct, indirect, operational, and recovery-related loss.

7. Why might a low residual score still matter?

Some low-scoring risks still deserve attention because of legal obligations, sensitive data handling, customer commitments, or concentration risk across multiple related systems.

8. When should I recalculate the risk?

Recalculate after major incidents, architecture changes, control upgrades, audit findings, vendor changes, or whenever threat conditions and business impact assumptions shift.