Case Fatality Rate Calculator

Work out case fatality rate instantly with clear inputs, formula shown and shareable results.

About Case Fatality Rate Calculator

Divides deaths by confirmed cases, the proportion of diagnosed cases that prove fatal.

Formula

Case fatality rate

CFR (%) = deaths among cases / confirmed cases x 100

Worked example

With the default values below, Case Fatality Rate Calculator returns Case fatality rate of 4.000%. Change any input above and every figure here is recalculated in your browser.

Inputs used

Deaths among casesaccepts 0–1,000,000: 60
Confirmed casesaccepts 1–100,000,000: 1,500

Results

Case fatality rate: 4.000%
Survival among cases: 96.000%
Deaths per 1,000 cases: 40.0
Cases per death: 25.0

Step by step

1Values used
2Case fatality rate
3Case fatality rate= 4.000
4Survival among cases= 96.000
5Deaths per 1,000 cases= 40.0
6Cases per death= 25.0

Assumptions and limits

The result is derived only from the 2 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why does CFR overstate lethality early in an outbreak?

Mild cases are undetected and deaths lag diagnosis, so the naive ratio is biased in both directions.

How does it differ from the infection fatality rate?

CFR uses diagnosed cases; IFR uses all infections including undetected ones and is always lower.