Quartile & IQR Calculator (Outliers)
Math ToolsQ1, median, Q3, IQR and outlier fences
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All history →Quartile & IQR Calculator (Outliers) — at a glance
Get the five-number summary and spot outliers.
3, 7, 8, 12, 13, 14, 18, 21, 40
Find Quartiles
Q1, Q2, Q3
IQR
Outliers
How to use it — step by step
A list of numbers separated by commas, spaces or new lines.
1
Add your text
Paste or type your input into the box. The Sample button fills in an example.
2
Press Find Quartiles
The result is made instantly inside your browser.
3
Copy the result
Use the Copy button, or send it to another tool.
Pro tips
Small things that make the result better.
✦Uses the inclusive method like Excel QUARTILE.INC.
✦Outliers lie beyond 1.5 × IQR from the quartiles.
✦Box plots are drawn from these five numbers.
Quick facts
Freeno signup
Privateruns in your browser
Instantresult in a second
No limituse it as often as you like
Frequently Asked Questions
What is the IQR?+
Q3 minus Q1. It measures the spread of the middle half of the data.
Which quartile method is used?+
Linear interpolation, the same as Excel’s QUARTILE.INC.
Is my data safe?+
Yes. Everything runs inside your own browser. Your text, files and images are never uploaded to any server.
Is this tool really free?+
Yes — completely free, no signup, no watermark and no usage limit.
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