Percentile Calculator
Find the percentile rank of a value in your data, or find the value at any percentile you choose. Pick your method and see every step.
Percentile Calculator
Choose what you want to find, enter your numbers and get your result instantly.
Step-by-Step Solution
What Is a Percentile?
A percentile tells you the position of a value within a data set. The 90th percentile is the value below which about 90% of the data falls. The 50th percentile is the median, with half of the data below it.
Percentiles are used a lot in test scores, growth charts and income data, because they show how a value compares with everyone else, not just how big it is.
Percentile Rank of a Value
The percentile rank answers the question: what share of the data is below this value? A common formula counts the values below x, adds half of the values equal to x, and divides by the total number of values.
Here L is the number of values less than x, S is the number of values equal to x, and n is the total number of values. Our calculator also shows the share of values strictly below x and the share at or below x, so you can match the version your teacher or textbook uses.
Finding the Value at a Percentile
To go the other way, you sort the data and find the position that matches the percentile. Different tools use slightly different rules for this, so our calculator offers three common methods:
- Interpolation (PERCENTILE.INC): the position is (n − 1) × p + 1, where p is the percentile as a fraction. If the position falls between two values, the result is blended between them.
- Exclusive interpolation (PERCENTILE.EXC): the position is (n + 1) × p. It only works when this position falls inside the data, so very low or very high percentiles may not be available for small data sets.
- Nearest rank: the position is p × n, rounded up to the next whole number. The result is always one of the values in your data.
For large data sets the three methods give very close answers.
Percentile Calculator Examples
Example 1: percentile rank
Four values (2, 4, 4, 4) are below 5, and two values (5, 5) equal 5. The percentile rank is (4 + 0.5 × 2) ÷ 8 × 100 = 62.5. So 5 is at about the 62.5th percentile.
Example 2: value at a percentile
With the interpolation method, the position is (10 − 1) × 0.25 + 1 = 3.25. The 3rd value is 30 and the 4th is 40, so the result is 30 + 0.25 × 10 = 32.5. With the nearest rank method, the position is 0.25 × 10 = 2.5, rounded up to 3, so the result is 30.
Example 3: the 90th percentile
For the same data, the interpolation position is 9 × 0.9 + 1 = 9.1. The 9th value is 90 and the 10th is 100, so the 90th percentile is 90 + 0.1 × 10 = 91.
Percentile vs Percentage
A percentage tells you how much of the total you got, such as 80% on a test. A percentile tells you how you did compared with others, such as being in the 80th percentile, which means you scored higher than about 80% of the people. A student can score 60% and still be in the 90th percentile if the test was very hard.
Percentiles and Quartiles
Quartiles are special percentiles. The first quartile (Q1) is the 25th percentile, the median is the 50th percentile, and the third quartile (Q3) is the 75th percentile. You can find them directly with our Quartile Calculator and Median Calculator.
More Percentile Examples
These extra worked examples show how to find a percentile rank, how the three methods can give different answers, and what to do when a method does not work. Remember that there is no single agreed rule for percentiles, so always check which method your teacher or software uses.
Example 4: Percentile rank of a test score
Ten students scored 55, 62, 68, 70, 74, 78, 81, 85, 90 and 96. Find the percentile rank of a score of 81.
Answer: a score of 81 is at the 65th percentile.
Six scores (55, 62, 68, 70, 74 and 78) are below 81, and one score (81 itself) is equal to 81. The percentile rank is (6 + 0.5 × 1) ÷ 10 × 100 = 65. If your textbook counts only the values strictly below x, the answer is 6 ÷ 10 × 100 = 60%. If it counts values at or below x, the answer is 7 ÷ 10 × 100 = 70%.
Example 5: Three methods, three answers
Find the 75th percentile of 12, 15, 21, 27, 30, 36, 42.
Answer: interpolation (INC) gives 33, while the exclusive method and nearest rank both give 36.
There are 7 values. Interpolation (PERCENTILE.INC): the position is (7 − 1) × 0.75 + 1 = 5.5. The 5th value is 30 and the 6th is 36, so the result is 30 + 0.5 × 6 = 33. Exclusive (PERCENTILE.EXC): the position is (7 + 1) × 0.75 = 6, so the result is the 6th value, 36. Nearest rank: 0.75 × 7 = 5.25, rounded up to 6, so the result is the 6th value, 36.
Example 6: When the exclusive method does not work
Find the 10th percentile of 3, 6, 9, 12, 15.
Answer: interpolation gives 4.2, nearest rank gives 3, and the exclusive method cannot find it.
There are 5 values. Interpolation: the position is (5 − 1) × 0.1 + 1 = 1.4, so the result is 3 + 0.4 × (6 − 3) = 4.2. Nearest rank: 0.1 × 5 = 0.5, rounded up to 1, so the result is the 1st value, 3. Exclusive: the position is (5 + 1) × 0.1 = 0.6, which is below 1, so it falls outside the data and the method gives no answer. For 5 values, the exclusive method only works for percentiles from about 16.67 to 83.33.
Example 7: A value that is not in the data
Find the percentile rank of 35 in 10, 20, 30, 40, 50.
Answer: 35 is at the 60th percentile.
Three values (10, 20 and 30) are below 35, and no value is equal to 35. The percentile rank is (3 + 0.5 × 0) ÷ 5 × 100 = 60. The value does not have to appear in the data to have a percentile rank.
Common mistakes when finding percentiles
A common mistake is confusing a percentile with a percentage: scoring in the 90th percentile does not mean scoring 90%. Another is forgetting to sort the data before finding the position. Also be careful to use the same method as your class or spreadsheet, because the methods can give different answers for small data sets. To find Q1, the median and Q3 directly, use our Quartile Calculator.
Created by Sajid Ali, SmartStatCalc · Last updated: 7 November 2026
Found a mistake or have a suggestion? Contact us.
How to Use Our Percentile Calculator
- Choose whether you want a percentile rank or the value at a percentile.
- Type or paste your data into the Data Values box.
- Enter the value x, or the percentile and the method.
- Click the Calculate Percentile button.
- Read the result and check the step-by-step solution.
Click Reset at any time to clear everything and start again. For a full summary of the same data, try the Descriptive Statistics Calculator.
Why Use SmartStatCalc?
SmartStatCalc is built to make everyday statistics quick and easy to understand. Instead of sorting and counting by hand, you can enter your data and see a clear result right away.
Who Can Use a Percentile Calculator?
Students use percentiles in statistics classes and to understand test results. Teachers use them to compare scores, and analysts and researchers use them to describe where a value sits within a large data set.
Frequently Asked Questions
What is the 90th percentile?
It is the value below which about 90% of the data falls.
Is the 50th percentile the same as the median?
Yes. The median is the 50th percentile of the data.
What is a percentile rank?
It shows what share of the data is below a certain value, so it tells you how a value compares with the rest.
Why do different tools give different percentiles?
There is no single agreed rule for finding positions between values, especially for small data sets. Our calculator lets you choose between three common methods.
Can a percentile be 0 or 100?
With the interpolation and nearest rank methods, the 0th percentile is the smallest value and the 100th percentile is the largest. The exclusive method does not allow these extremes.
Is a higher percentile always better?
It depends on what you measure. A high percentile for test scores is good, but a high percentile for something like waiting time is not.
Does the value have to be in my data?
No. You can find the percentile rank of any value, even if it does not appear in your data.
Is this Percentile Calculator free?
Yes. SmartStatCalc's Percentile Calculator is free to use online.
Contact SmartStatCalc
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Cite this calculator
If you use this calculator in your work, you can cite it like this:
SmartStatCalc. (2026). Percentile Calculator. https://smartstatcalc.com/percentile-calculator/