Every Excel error code points to a specific cause. Once you know the cause, the fix is usually quick.
#N/A: value not found
A lookup could not find its value. Check for extra spaces, numbers stored as text, or a typo. Use =IFNA(VLOOKUP(...), "Not found") to show a clean message.
#VALUE!: wrong type of data
The formula tried to do maths on text, or ranges are different sizes. Look for hidden spaces or text in number columns. =VALUE(A1) can convert text to a number.
#REF!: broken reference
The formula points to a cell that was deleted. Press Ctrl+Z straight away if you just deleted something. Otherwise edit the formula and re-select the range.
#DIV/0!: division by zero
The divisor is zero or blank. Use =IF(B2=0, 0, A2/B2) or =IFERROR(A2/B2, 0).
#NAME?: Excel does not recognise something
A function name is misspelled, text is missing quotes, or a named range does not exist. Check spelling, such as VLOOKPU instead of VLOOKUP.
#NUM! and #NULL!
- #NUM!: the number is invalid or too large.
- #NULL!: a missing comma or colon between ranges.
IFERROR vs IFNA
IFERROR hides every error, which can hide real mistakes. IFNA only hides #N/A, so use it for lookups.