Decile Calculator

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

About Decile Calculator

Deciles split ordered data into ten equal parts, so the kth decile is the value below which k tenths of the data fall. Linear interpolation between neighbouring observations is used when the position is not a whole index.

Formula

Decile position

position = (n − 1) × k/10, then interpolate between the surrounding values

Worked example

With the default values below, Decile Calculator returns The requested decile of 22.90000000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Data values: 12, 15, 18, 22, 25, 28, 31, 35, 38, 42, 47, 53
Which decile (1 to 9)accepts 1–9: 3

Results

The requested decile: 22.90000000
First decile D₁: 15.30000000
Ninth decile D₉: 46.50000000
Interdecile range D₉ − D₁: 31.20000000

Step by step

1Values used
2Decile position
3The requested decile= 22.90000000
4First decile D₁= 15.30000000
5Ninth decile D₉= 46.50000000
6Interdecile range D₉ − D₁= 31.20000000

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 8 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 third decile of the sample?

The position is 11 × 0.3 = 3.3, interpolating between the fourth and fifth sorted values to give 22.9.

How do deciles relate to percentiles?

The kth decile is the 10k-th percentile, so D₅ is the median.