How can I identify the specific cell causing an error within a complex formula in Google Sheets?

Use the `ARRAYFORMULA` and `IFERROR` functions in combination. Wrap the problematic part of your formula within `ARRAYFORMULA` and then use `IFERROR` to highlight the cells causing the error. For example, `=ARRAYFORMULA(IFERROR(A1:A10/B1:B10, "Error"))` will show "Error" in any cell where the division results in an error, helping you pinpoint the issue. You can also use the 'Evaluate formula' feature in Tools -> Script editor to step through the formula's calculations.