Data collection

Cleaning Data in Excel

About this course

Anyone with a little experience in working with data knows: data often is messy. Datasets with errors, missing values, wrong formatting: before beginning an analysis or visualising data, there is a lot of work in cleaning and transforming data.

For very small data sets it often makes sense to do the cleaning and transforming manually. You can just type in the correct data or make some calculations yourself. But when the data set you are working with contains tens, hundreds, thousands or even more lines, this manual approach is no longer feasible. It would just take up to much time and the risk of making errors becomes too big.

So for cleaning up larger data sets, you need tools. And there are some very powerful tools out there that can clean up data. But most of them are aimed at advanced users: very often programming skills are needed. As this course isn’t aimed at programmers, we are going to use an everyday tool a lot of people already are familiar with: Microsoft Excel.

So in this course we'll introduce and demonstrate some useful Excel commands and formulas for cleaning up and transforming data. But you’ll also learn some strategies and tricks for managing your data cleaning processes.

No prior knowledge is needed, but a little knowledge of Microsoft Excel will come in handy.

In a nutshell

Skill level



1 hr 27 min



Students enrolled


Meet your instructor: Maarten Lambrechts

Maarten Lambrechts

Data visualisation consultant


Data journalist, data designer, visualisation consultant

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