#DIV/0!
What it means. You are dividing by zero, or by an empty cell.
How to fix it. Check the cell you are dividing by. If it can legitimately be empty, wrap the formula in IFERROR, for example =IFERROR(C5/$C$9,"").
The Excel error decoder
Excel errors look scary, but each one is trying to tell you something. Here is what they mean and how to fix them.
#REF!
What it means. The formula points at a cell that no longer exists, usually because a row or column was deleted.
How to fix it. Press Ctrl + Z straight away to undo the delete. If it is too late, click into the formula and point it back at the right cell.
#NAME?
What it means. Excel does not recognise something in your formula.
How to fix it. Check the spelling of the function name, put text in quotation marks, and check your version of Excel has the function. Newer functions, such as XLOOKUP, need Microsoft 365.
#VALUE!
What it means. The formula is trying to use the wrong kind of value, such as text where it expects a number.
How to fix it. Check the cells you are using. Look for stray spaces or text hiding in your numbers.
#N/A
What it means. A lookup could not find what you asked for.
How to fix it. Check the spelling and look for extra spaces. If a missing match is fine, use IFNA to show something friendlier, such as "Not found".
#SPILL!
What it means. The formula wants to fill several cells, but something is in the way.
How to fix it. Clear the cells below or beside the formula so its results have room to spill.
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What it means. This one is not really an error. The column is too narrow to show the number.
How to fix it. Double-click the line between the column letters to make the column fit its contents.
We work through errors like these on my Intermediate Excel course.