Measuring Usability
Quantitative Usability, Statistics & Six Sigma by Jeff Sauro

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 Measuring Usability LLC, a company providing statistics and usability consulting to Fortune 1000 companies.
He is the author of over 20 journal articles and 4 books on statistics and the user-experience.
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Posted Comments

There are 6 Comments

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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Jeff's Books

Quantifying the User Experience: Practical Statistics for User ResearchQuantifying the User Experience: Practical Statistics for User Research

The most comprehensive statistical resource for UX Professionals

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

Detailed Steps to Solve over 100 Examples and Exercises in the Excel Calculator and R

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A Practical Guide to the System Usability ScaleA Practical Guide to the System Usability Scale

Background, Benchmarks & Best Practices for the most popular usability questionnaire

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A Practical Guide to Measuring UsabilityA Practical Guide to Measuring Usability

72 Answers to the Most Common Questions about Quantifying the Usability of Websites and Software

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