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- Finds the value at any percentile of a data set, such as the 90th percentile.
- Finds the percentile rank of a value, such as where a score of 35 falls.
- Gives the five-number summary: minimum, Q1, median, Q3 and maximum, plus the IQR.
- Uses linear interpolation, the same method as Excel PERCENTILE.INC, with the nearest-rank result for comparison.
How to use the percentile calculator
Paste your data
Enter numbers separated by commas, spaces or new lines. They do not need to be sorted.
Choose what to find
Pick the value at a percentile, or the percentile rank of a value.
Enter the percentile or value
For example 90 for the 90th percentile, or a score of 35 to rank it.
Read the result
The answer appears with the quartiles, IQR, outlier fences and full working.
How percentiles are calculated
Value at the p-th percentile
Sort the data from smallest to largest
Position = p ÷ 100 × (n − 1) + 1
If the position falls between two values, interpolate between them
This is the inclusive method used by Excel PERCENTILE.INC and many statistics packages.
Percentile rank of a value
Percentile rank = (number below + ½ × number equal) ÷ n × 100
Counting half of the equal values is the standard way to handle ties.
Example 1: the 40th percentile
Data: 15, 20, 35, 40, 50 (n = 5).
- Position 0.40 × 4 + 1 = 2.6
- Between the 2nd and 3rd values 20 and 35
- Interpolate 20 + 0.6 × (35 − 20) = 29
- Nearest-rank method 20
Different methods can give different answers for small data sets, which is why both are shown.
Example 2: quartiles of 1 to 10
Data: 1, 2, 3, … 10.
- Q1 (25th) 3.25
- Median (50th) 5.5
- Q3 (75th) 7.75
- IQR 4.5
- 90th percentile 9.1
The IQR covers the middle 50% of the data and is not affected by extreme values.
Example 3: percentile rank
Where does 35 fall in 15, 20, 35, 40, 50?
- Values below 2
- Values equal 1
- Percentile rank (2 + 0.5) ÷ 5 × 100 = 50%
A value of 45 would sit at the 80th percentile.
Where a percentile calculator helps
Test scores
See what share of students scored below a given mark.
Salaries and prices
Find the 25th, 50th and 75th percentile of pay or house prices.
Website and app speed
Report the 90th or 95th percentile of load times.
Growth and health data
Understand where a measurement sits within a group.
To flag outliers with the 1.5 × IQR rule, try the upper and lower fence calculator. For percentiles of a normal distribution, use the z-score calculator, and for the mean and median, the average calculator.
Percentile calculator FAQ
What is a percentile?
A percentile tells you the value below which a given percentage of the data falls. The 90th percentile is the value that 90% of the data is below.
What is the difference between a percentile and a percentage?
A percentage is a share out of 100. A percentile is a position within a data set. Scoring at the 80th percentile means you did better than about 80% of the group, not that you got 80% of the questions right.
How do I find the IQR?
Subtract the first quartile from the third quartile: IQR = Q3 − Q1. The calculator shows both quartiles and the IQR.
Why do calculators give different percentile answers?
There are several accepted methods. This calculator uses linear interpolation (PERCENTILE.INC) and also shows the nearest-rank result.
Is the 50th percentile the median?
Yes. The 50th percentile and the median are the same value.
How many numbers can I enter?
Up to 10,000 values.