[INTERNAL LAB]

A CIRCULAR REFERENCE in Excel:
cell01 depends on cell02, and cell02 depends back on cell01. Excel can’t calculate a loop like that normally, so it usually shows a warning and/or returns 0.

Example:

A1: =B1+1 B1: =A1+1

This is circular because A1 needs B1, and B1 needs A1.

How to find it

• Look in the Status Bar at bottom-left: it may say Circular References: A1.
• Or go to Formulas → Error Checking → Circular References.
• Use Formulas → Trace Precedents / Trace Dependents to see the loop.

How to fix it

Break the loop:

1. Make one cell an input instead of a formula

   A1: 10 B1: =A1+1

2. Use a third cell as the source

   C1: 10 A1: =C1+1 B1: =C1+2

3. Paste one formula as a value
   • Copy the cell → Paste Special → Values
   • Then remove the circular formula.
4. Check named ranges
   • Go to Formulas → Name Manager.
   • If cell01 and cell02 are names, they may refer to each other.

If the circular reference is intentional

You can enable iterative calculation:

• File → Options → Formulas → Enable iterative calculation
• Set Maximum Iterations and Maximum Change

But only do this if the loop is supposed to converge. If the equations are inconsistent, Excel may never settle on a correct answer.

Example:
A1 = B1+1 and B1 = A1+1 has no solution.
A1 = B1+1 and B1 = A1-1 has infinite solutions, so Excel still needs a starting value.

If you share the exact formulas in cell01 and cell02, I can tell you how to rewrite them correctly.