Clean data quickly with Flash Fill

Excel has many powerful & time-saving features. Even by Excel’s standard, Flash Fill is magical. Introduced in 2013, Flash Fill is a rule engine to Excel’s fill logic. Every time you type something in a cell, Excel will try to guess the pattern and offers to fill up the rest of cells for you. That is some serious time saving magic.

Let’s understand what Flash Fill is and few sample use cases.

Flash Fill, a smart rule engine

Flash fill listens to your every key stroke and tries to guess what you are doing. Remember Clippy from Office 97? Think of Flash Fill as Clippy’s less annoying & invisible cousin. Once Flash Fill identifies a pattern in your data entry, it offers a way to type rest of the data for you. If you accept the suggestion, the rest of the cells are automatically filled up.

Flash fill may not be a convenient option for simple patterns (like 1,3,5… or a bunch of dates or month names). But once you go beyond the realm of simple patterns, Flash Fill can be very useful.

Especially, when it comes to cleaning data.

Example 1 – Extracting numbers from text

Let’s say you are looking at some text data and want to extract the number portion.

Now, there is no simple way to do this. Any formula or VBA approach can be tedious.

But see what happens when you unleash Flash Fill on this unruly data.

Example 2 – Extracting first name from list of names

Again, writing a formula can be tricky ( LEFT(name, FIND(" ",name)) should work – more here).

But Flash Fill is faster and simpler. Just type the first few names and let Flash Fill do its magic.

Example 3 – Writing a bunch of formulas

Humor me with a scenario where you have customer names and you must lookup some corresponding data. Obviously you plan to use VLOOKUP for this. But the lookup table has other plans. Instead of customer name, the lookup table has firstname-initial_of_lastname.  So for Bill Gates, the lookup table lists the name as Bill-G.

Of course, you can write a complex VLOOKUP. But why bother? Use Flash Fill to do the dirty work for you.

See below illustration to understand how this works.

Once the lookups are written, you can use FIND REPLACE (Ctrl+H) to add = at the front.

Flash Fill tips & tricks:

• Press CTRL+E to trigger flash fill. Excel will look at previously typed data and guesses the rest.
• To ignore Flash Fill suggestion, press ESC.
• By default, Flash Fill will be always listening and offers suggestions whenever it can. If you want to disable this, Use File > Options > Advanced and uncheck “Automatically Flash Fill” option. Click here for a screenshot of this process.

Do you Flash Fill?

Flash Fill is a fun and powerful way to clean data and get what you want. I use it often, when dealing with complex datasets.

What about you? Do you Flash Fill? When do you use it? Please share your tips and use cases in the comments.

If you have never Flash Filled, go ahead and try it today. See the magic yourself and share your story in the comments.

Remember, your comments on this post qualify for $31 amazon gift card giveaway.

More fun & powerful ways to fill data:

If you like Flash Fill, check out below tutorials for more powerful ways to automate data entry & cleanup processes.

• Unleash pattern power fill Excel auto fill
• Quickly fill all blank cells in a table with data
• How to convert text to dates

This post is part of our Awesome August Excel Festival.