How to identify missing numbers sequence in Excel?

Let's say you have a long list of sequence numbers to mark items, such as check numbers in bank statements, normally we scrolling through and locate the missing sequence numbers manually. Sometimes this is quite arduous and time-consuming. You may think of tricky ways to deal with it. Yes, there are several easy ways to identify and locate missing numbers sequence in Excel 2007, Excel 2010, and Excel 2013 quickly and conveniently.

Identify missing numbers sequence with IF formula

Identify missing numbers sequence with an array formula

Identify missing numbers sequence with Kutools for Excel quickly

Identify missing numbers sequence with IF formula

As we all known, most of sequence numbers are with fixed increment of 1, such as 1, 2, 3, …, N. Therefore, if you can identify the number is not less 1 than its following number, there is a missing number.

We will show you the tutorials with an example as following screenshot shows:

1. In a blank cell, enter the formula of =IF(A3-A2=1,"","Missing"), and press the Enter key. In this case, we enter the formula in Cell B2.

If there is no missing numbers, this formula will return nothing; if missing numbers exist, it will return the text of "Missing" in active cell.

2. Select the cell B2 and drag the fill handle over the range of cells that you want to contain this formula. Now it identifies the missing numbers with the text of "Missing" in corresponding cells of Column B. See the following screenshot:

Identify missing numbers sequence with an array formula

Sometimes it requires not only identifying missing numbers sequence, but also listing missing numbers too. You can deal it with following steps:

1. in the adjacent cell, please enter the formula = SMALL(IF(ISNA(MATCH(ROW(A$1:A$30),A$1:A$30,0)),ROW(A$1:A$30)),ROW(A1))

A1:A30 = range of numbers, the sequence to check against is from 1 to 30

2. Press the Ctrl + Shift + Enter Keys together to finish the formula. Copy down the formula until you get #NUM! errors meaning all missing numbers have been listed. See screenshot:

Identify missing numbers sequence with Kutools for Excel quickly

The above methods only can identify the missing pure number sequence, if you have the sequence such as AA-1001-BB, AA-1002-BB, they may not work successfully. But, don't worry, Kutools for Excel’s powerful feature – Find Missing Sequence Number can help you quickly identify the missing sequence.

After installing Kutools for Excel, please do as this:

1. Select the data sequence that you want to find the missing sequence.

2. Click Kutools > Insert > Find Missing Sequence Number, see screenshot:

3. In the Find Missing Sequence Number dialog box:

(1.) If you choose Inserting new column with following missing marker option, all the missing sequence numbers have been marked with the text Missing in a new column next to your data. See screenshot:

(2.) If you choose Inserting missing sequence number option, all the missing numbers have been inserted into the sequence list. See screenshot:

(3.) If you choose Inserting blank rows when encounting missing sequence numbers option, all blank rows are inserted when there are missing numbers . See screenshot:

(4.) If you choose Fill background color option, the location of the missing numbers will be highlighted at once. See screenshot:

Demo: Identify missing numbers sequence with Kutools for Excel quickly