CVSS v4.0 & v3.1 Calculator
Calculate CVSS v4.0 and v3.1 severity scores. Build or validate vectors, including optional v4.0 metrics.
Base metrics
Threat metrics (Optional metrics)
Environmental metrics (Optional metrics)
Supplemental metrics (Optional metrics)
Supplemental metrics add context and do not change the score.
How it works
Choose v4.0 or v3.1, select metrics or paste a complete vector. The version is detected when a vector is applied. Version 4.0 uses the FIRST reference calculator and supports Base, Threat, Environmental and Supplemental metrics; optional groups are expandable. Version 3.1 retains the eight-metric base calculation and prescribed rounding.
Scores and canonical vectors can be copied or exported as CSV. CVSS describes severity, not exploitation probability or business risk. The v4.0 result is labelled CVSS-B, CVSS-BT, CVSS-BE or CVSS-BTE according to the configured groups; Supplemental metrics do not change the score. Version 3.1 temporal/environmental vectors are not supported. Everything is calculated in your browser.