Decile Calculator

What Are Deciles?

Deciles split an ordered dataset into ten equal-sized groups. The nine cut points D1 through D9 mark the 10th through 90th percentiles. D5 is the median (50th percentile), and values above D9 sit in the top tenth of the distribution.

Decile Formula

For a sample of size $n$, the position of the $k$th decile is:

$$\text{position} = \frac{k(n + 1)}{10}$$

where $k = 1, 2, \ldots, 9$. If the position is not an integer, the calculator linearly interpolates between the surrounding ordered values.

How to Use This Calculator

Paste at least nine numbers (commas, spaces, or newlines). Results show D1–D9, each percentile rank, and the fractional position used for interpolation. Compare with the Quartile Calculator and Percentile Calculator when you need coarser or finer ranking.

Example

For the twelve values $12, 18, 5, 22, 9, 31, 14, 27, 3, 40, 7, 19$, the ordered list starts $3, 5, 7, \ldots$ and D1 sits near the lower end while D9 sits near the upper end. D5 summarizes the center of the sample.

Related Tools

Explore related statistics tools:

• Quartile Calculator
• Percentile Calculator
• Average Calculator