What does quartile mean?
A quartile is one of four groups into which a population, list, or set of measurements is divided, with each group containing approximately one quarter of the total. The expression is especially common in statistics, where ranked observations are split at the 25th, 50th, and 75th percentiles. These boundaries create the first, second, and third quartiles, while the upper quartile identifies the highest 25 percent of a distribution. Writers also use phrases such as 'top quartile' to describe leading institutions, investments, products, or performers. For example, a university may report that it places students in the top quartile for graduation rates. Although the word is related to 'quarter,' it usually emphasizes an ordered division into four sections rather than simply the amount equal to one-fourth. In everyday use, it conveys the idea of standing among the leading 25 percent, often suggesting strong performance or membership in an elite group.
nounOne of four equal groups into which a population, set of observations, or ordered list is divided, each containing approximately one quarter of the total. In statistics, the term also refers to the range of values between the 25th and 50th percentiles or between the 50th and 75th percentiles.
- Any one of four equal groups into which a population or collection is divided.
- In statistics, a value range or group occupying one quarter of an ordered distribution, especially when referring to the first, second, or third quartile.
- The upper or lower 25 percent of a ranked distribution, as in 'the top quartile' or 'the bottom quartile'.
"The fund's returns placed it in the top quartile among comparable investments."
"A score in the upper quartile indicates performance among the highest 25 percent of the group."
"The study compared income distributions by dividing the data into quartiles."
The plural is used when referring to several of the four equal groups into which a population or dataset has been divided.
"The researchers compared the upper quartiles of income across the four regions."
In ranked data, the top quartile is the highest-performing 25 percent, putting you ahead of roughly three-quarters of the group.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does quartile come from?
Quartile entered English from French quartil, a word meaning a fourth part. The French term was based on Latin quartilis, meaning 'of or belonging to the fourth part,' which derives from quartus, 'fourth.' Quartile was initially used in statistical contexts before becoming common in broader descriptions of ranked populations and performance.
Related word forms
How quartile is actually used
The term is especially common in statistics, economics, education, and performance analysis. In general use, 'top quartile' often means the highest-performing 25 percent, while 'first quartile' can ambiguously mean either the first 25 percent or the 25th-percentile boundary; context usually determines the intended meaning.
Easily confused with quartile
A quarter is one-fourth of a whole, whereas a quartile is one of four groups or sections into which a population or ordered set of data is divided.