Usability, Customer Experience & Statistics

Confidence Interval Calculator

Jeff Sauro • March 21, 2012

Compute confidence intervals around continuous data using either raw or summary data.

Enter Summarized Data
Sample Data
Confidence Level :

Show Sample Data
NMeanStDevSE Mean

About Jeff Sauro

Jeff Sauro is the founding principal of MeasuringU, a company providing statistics and usability consulting to Fortune 1000 companies.
He is the author of over 20 journal articles and 5 books on statistics and the user-experience.
More about Jeff...

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Posted Comments

There are 8 Comments

May 16, 2016 | Earl wrote:

this calc is for a complete set of raw data. if you only have a sample you need a different calculator 

August 16, 2015 | Grady wrote:

.needs to give accurate readings, like measure at LEAST to the nearest thousandth 

April 30, 2013 | Carlos Bento wrote:

I fill easy to use and quick 

July 15, 2012 | Yoda wrote:

This was WAY off 

May 19, 2012 | Mara wrote:

take home* 

May 19, 2012 | Mara wrote:

I just used this to check my answers for a take hoe final and it was only a few decimals off, awesome! 

May 10, 2012 | mark wrote:

helped me out while taking a final 

April 19, 2012 | wayne wrote:

excellent calculator  

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Excel & R Companion to Quantifying the User ExperienceExcel & R Companion to Quantifying the User Experience

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