Pooled Testing Efficiency Calculator

Work out pooled testing efficiency instantly with clear inputs, formula shown and shareable results.

About Pooled Testing Efficiency Calculator

Applies Dorfman two-stage pool testing: one test per pool plus individual retests whenever a pool is positive.

Formula

Dorfman pooling

Tests per person = 1/k + (1 - (1 - p)^k); the approximate optimal pool size is 1/sqrt(p)

Worked example

With the default values below, Pooled Testing Efficiency Calculator returns Tests required per person of 0.2829. Change any input above and every figure here is recalculated in your browser.

Inputs used

Samples per poolaccepts 2–100: 10
Prevalenceaccepts 0.01–40: 2

Results

Tests required per person: 0.2829
Probability a pool tests positive: 18.293%
Testing capacity saved: 71.71%
Approximate optimal pool size: 7.1

Step by step

1Values used
2Dorfman pooling
3Tests required per person= 0.2829
4Probability a pool tests positive= 18.293
5Testing capacity saved= 71.71
6Approximate optimal pool size= 7.1

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

When does pooling stop helping?

Above roughly 25 to 30% prevalence almost every pool is positive, so pooling costs more tests than it saves.

Does pooling reduce sensitivity?

Yes, dilution raises the detection threshold, which limits practical pool sizes for low viral loads.