Quadrat Sampling Density Calculator

Work out quadrat sampling density instantly with clear inputs, formula shown and shareable results.

About Quadrat Sampling Density Calculator

Divides the total count by the area sampled across all quadrats to give density per square metre and per hectare.

Formula

Quadrat density

Density = total individuals / (number of quadrats x area per quadrat); per hectare = density x 10,000

Worked example

With the default values below, Quadrat Sampling Density Calculator returns Density of 58.0000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Individuals countedaccepts 0–1,000,000: 145
Quadrats sampledaccepts 1–1,000: 10
Area of each quadrataccepts 0–10,000 m2: 0.25 m2

Results

Density: 58.0000 per m2
Density: 580,000.0 per hectare
Mean count per quadrat: 14.500
Total area sampled: 2.500 m2

Step by step

1Values used
2Quadrat density
3Density= 58.0000 per m2
4Density= 580,000.0 per hectare
5Mean count per quadrat= 14.500
6Total area sampled= 2.500 m2

Assumptions and limits

The result is derived only from the 3 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

How many quadrats are needed?

Enough for the running mean to stabilise; a common rule is to sample until the standard error falls below 10% of the mean.

Where should quadrats be placed?

At random or systematically with a random start, never in places chosen because they look representative.