Charlson Comorbidity Index calculator

The Charlson Comorbidity Index (CCI) captures the overall burden of comorbid conditions and prognosis. Enter age and check the conditions present — the calculator sums their weights, adds an age adjustment and shows the total score with a 10-year survival guide. It is a prognostic tool for clinicians and research, not a diagnosis.

Calculate the Charlson index

1 point
2 points
3 points
6 points

Enter age and check the conditions — the index appears instantly.

Charlson index and prognosis

A 10-year survival guide by total score (Charlson formula). Values are approximate and depend on many factors; a doctor makes the assessment.

Total score10-year survival (guide)
0≈ 98%
1–2≈ 90–96%
3–4≈ 53–77%
5 and above< 21%

What the Charlson index is

The Charlson Comorbidity Index (CCI) expresses the total “burden” of comorbid conditions as a single number. Each condition has a weight (1, 2, 3 or 6 points) reflecting how strongly it affects prognosis.

It is widely used in medicine and research to compare patients by comorbidity severity and to estimate long-term prognosis.

How it is calculated

The points of all checked conditions are summed, then an age adjustment is added — 1 point per decade over 40 (maximum 4 at 80+). The total reflects both conditions and age.

Only the more severe of a pair is counted: diabetes with organ damage instead of plain diabetes, severe liver disease instead of mild, metastatic instead of localized tumor — the calculator does this automatically.

What the score means

The higher the index, the heavier the background disease and the worse the prognosis. In Charlson’s original work the estimated 10-year survival falls as the score rises: about 98% at 0, and much lower at 5 and above.

It is a statistical estimate for groups, not a prediction for an individual: the personal outcome depends on treatment, disease course and many other factors.

What it is used for

The index helps assess surgical and long-term risk, stratify patients in research and plan follow-up. It is often computed alongside other scores.

Management decisions are made by a doctor from the whole clinical picture, not the index alone.

A prognostic estimate, not a diagnosis

The calculator does not diagnose and does not replace a doctor. Condition checkboxes should rely on confirmed diagnoses, and a specialist interprets the result.

Frequently asked questions

  • Enter age and check the conditions present. The calculator sums their weights (1–6 points), adds 1 point per decade over 40, and shows the total with a 10-year survival guide.

  • An age adjustment is added to the condition points: +1 per full decade over 40 (50–59 → +1, 60–69 → +2, 70–79 → +3, 80+ → +4). This is the standard age-adjusted index.

  • Only the more severe of a pair is counted: diabetes with organ damage (2) instead of plain (1), severe liver disease instead of mild, metastatic instead of localized tumor. The calculator handles this.

  • Higher means heavier comorbidity and lower estimated survival. Roughly: 0 — very good prognosis, 3–4 — moderately reduced, 5+ — poor. It is a group estimate, not an individual prognosis.

  • No. It is a prognostic scale based on already-known diagnoses. A doctor interprets the result and makes decisions.

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This calculator is for reference and information only and is not a diagnosis. Comorbidity and prognosis are assessed by a doctor.