Prevalence Rate Calculator

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

About Prevalence Rate Calculator

Divides existing cases by the population examined to give point prevalence, expressed as a percentage, per 1,000 and per 100,000.

Formula

Prevalence

Prevalence = existing cases / population examined; odds = prevalence / (1 - prevalence)

Worked example

With the default values below, Prevalence Rate Calculator returns Point prevalence of 3.750%. Change any input above and every figure here is recalculated in your browser.

Inputs used

Existing casesaccepts 0–10,000,000: 450
Population examinedaccepts 1–1,000,000,000: 12,000

Results

Point prevalence: 3.750%
Cases per 1,000: 37.50
Cases per 100,000: 3,750.0
Odds of disease: 0.0390

Step by step

1Values used
2Prevalence
3Point prevalence= 3.750
4Cases per 1,000= 37.50
5Cases per 100,000= 3,750.0
6Odds of disease= 0.0390

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 4 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

What is the relationship to incidence?

In a steady state, prevalence is approximately incidence multiplied by average disease duration.

Point or period prevalence?

Point prevalence counts cases at one moment; period prevalence counts anyone with the condition during an interval.