Data validation in Excel
Data validation is a feature of Excel that controls what a user can enter in Excel cells. Basically, it is used in Excel to restrict the type of data/value to be entered in the Excel cells. In Excel, you can use predefined data validations as well as define your own custom conditions.
For example, use the number data validation on a column to restrict the user to enter only numeric data in the cell of the respective column. Similarly, there is various type of data validation to be put in Excel.
Several types of data validations are used in Excel. The most commonly used data validation is to create a dropdown list. The advantage of using data validation in an Excel worksheet is that - it stops the users from entering invalid data into the Excel table.
In this chapter, we will brief you on data validation. In the next chapter, you will see how actually the data validations are applied on Excel cells.
Advantages of using data validations
There are various advantages of using data validations on Excel cells, some of them are as follows:
What happens when data validation applies?
When you apply data validation on an Excel worksheet, it restricts the users from entering any unnecessary input to the cells. For example, if you put the number validation on a cell/column, then you are not allowed to enter any other type of input in it.
If you try to input the wrong data type of input, a message automatically displays by the data validation that which type of data the respective cell will accept. This message is a customized message, which is created while putting validation on the Excel worksheet.
By applying data validation, you can stop the user from entering the unreasonable input into the Excel worksheet.
Excel data validation examples
In Excel, you can put several types of data validations on Excel cells, such as -
These all are predefined data validations. Besides the predefined data validations, which are offered by the Excel, you can also define the custom validations on data to be entered in Excel worksheet.
We will show you the example of each validation.
The number validation allows the users to enter only numeric values to the cell. When this validation applies to a particular cell/column, you are not allowed to enter any other type of data in it. For example, Age validation: Enter the age greater than 18 only.
Decimal number Validation
Decimal numbers are floating-point numbers that contain a decimal point in them. When the decimal number validation applies on an Excel worksheet, only numbers having a decimal point are allowed to enter into that Excel worksheet. For example, 1.25, 8.9754, 2.9, etc.
Length validation restricts the users to enter the input length more than the specified number in the validation. For example, you set the length validation on a cell to 8, then the users are not allowed to enter the data having more than 8 characters/numbers in it.
This validation limits the number of characters or digits to be entered in the restricted cells.
Date and time validation
Date and time validations are the validation applied on the column where you want to restrict the users to enter only date and type of input in it. You can individually apply date and time validations to two different columns.
This will allow the user to enter only the date and time type of input value in the restricted column. For example,
Date - Enter a date only between January 01, 2020, and January 01, 2021.
Time - Enter a time only between 9:30 AM to 6:30 PM.
Excel input validation (dropdown list)
This is a bit different validation from all the other validations mentioned above. It is an input validation that presents predefined choices to the users to enter the input to an Excel cell. Hence, you have the only option to provide input to an Excel cell is to choose input value from the dropdown list.
Dropdown list creation is the most commonly used data validation. E.g., A gender dropdown list having only three options - Male, Female, and Other.
You can also enter the value to the validated field manually. But if it does not meet with any of the specified values in the list, it will generate a default alert message.
Custom data validation
Besides all these built-in validation rules, user can also set their own custom validations using their formulas. You can create custom validations in Excel. These custom validations require a formula to be entered by the creator.
You can define the custom condition from the settings tab by choosing Custom in the validation criteria. We will discuss it later, below in this chapter.
Defining data validation Rules
In Excel, navigate to the Data tab, where inside the Data Tools section, you will get a Data Validation option. Data > Data Tools > Data Validations
From here, you can set data validation rules. Data validation panel has three tabs to set its rules, i.e., Settings, Input Message, and Error Alert.
Following are the three tabs:
A setting tab is a place where you define the validation criteria for a column/cell. This tab contains several built-in validation rules to choose. It also has a Custom data validation option to define your own custom rule. You can choose it too and use your own formula to put the validation.
Input Message tab
The input message tab contains two fields where you can provide a title and a message for the users. This message displays to the users when a cell with the validation rule is selected. It is just a message nothing else, which appears when a cell with validation rule is selected. It indicates to the users before inputting the data into cells.
It is completely optional to provide a message. No message will appear if you set no input message.
Error Alert tab
The error alert tab is a dialogue box, which appears when a wrong entry is filled. It basically shows an error message to the users when they provide the wrong type of input value. It can stop the process of entering the data till correction.
In the Style field, you have set "Stop" and provide a message in the Error message field. Hence, the user tries to input the wrong value, input is not allowed and an error message will appear like as showing below:
When the Style is set to another option, like Warning or Information, a different icon will display with a custom message. The below table will summarize the alert type, which are of three types: Stop, Warning, and Information.