Validation feature is used to control data that can be entered into a particular cell. Let's say we want to allow users to enter numbers between 1 and 5 into cell F7. Select Validation from Data menu
A data validation dialog box will appear. There aremany options listed on data validation dialog box. Make sure the target cell F7 is selected in 'Range' box. If not, click '<-' button to select the target cell.
Select 'Decimal' from the 'Allow:' option box. After that 'Data:' box will automatically be populated with available options. Select 'between'.
Then enter numbers '1' and '5' in boxes 'minimum' and 'maximum'. You can also customize the message the user will receive when a number outside this range is entered. Use 'message' box to enter your custom message. When done, press 'OK' button to activate cell validation.
Once the validation is active, if a restricted value is entered in cell F7 system will display a message as show below. The user will be forced to enter a valid number.
