You can customize the field (column) type in the field customization menu. To open the field customization menu, click on the menu icon in the column header you want to customize, and select the "Customize field type" option. Alternatively, you can double-click on the field header to open the customization menu.
After clicking "Customize field type," click on the field type button to open the menu of different field types. After selecting a new field type, be sure to click the blue "Save" button—otherwise,b your type changes will not be saved.
Different field types have different customization options. Checkbox fields, for example, have no additional customization options:
Number fields, on the other hand, allow you to set whether the numbers should be formatted as integers or decimals, whether or not to allow negative numbers, and whether or not to set a default field value. For more information on each field type, check out our guide to field types.
Airtable does its best to convert existing cell values to the new type during a field conversion, but some conversions may not be possible with certain types. For example, converting a text field to an attachment field will clear all the text values, since plain text values do not represent an attachment. If you see that you have lost some cell values during a conversion, you can undo your change to return the field to its previous state (and restore the data that was lost due to the conversion).