A circular reference occurs when two or more cells in a spreadsheet contain formulas that reference each other, either directly or indirectly. This can cause the spreadsheet to calculate incorrect results or even crash. To avoid circular references, you should always make sure that the cells in your spreadsheet are referencing other cells that contain values, not formulas.
Circular references can be difficult to spot, especially in large spreadsheets. However, there are a few things you can look for to identify them. One is to look for cells that contain the #REF! error. This error indicates that the cell is referencing another cell that contains a circular reference. Another thing you can look for is cells that are highlighted in green. This highlighting indicates that the cell is part of a circular reference.