Free formula checker

Fix your Excel formula errors — free.

Upload a spreadsheet and we’ll find every formula that’s broken or throwing an error — #REF!, #DIV/0!, #VALUE!, #NAME?, #SPILL! — tell you in plain English what each one means and the likely cause, and flag the ones that still calculate a wrong answer. Nothing is changed without showing you first.

Free · no signup · your file is never stored
fix-formula-errors · xlsx-for-ai

What these errors mean

Excel shows an error token in a cell when a formula can’t return a valid answer. The most common ones:

  • #REF! — the formula points at a cell, row, column, or sheet that was deleted or moved.
  • #DIV/0! — it divides by zero, or by a cell that’s empty.
  • #VALUE! — a value is the wrong type: text where a number is expected.
  • #NAME? — an unrecognized name — a misspelled function or a named range that doesn’t exist.
  • #SPILL! — a dynamic-array formula can’t expand because something is already in the cells it needs.
  • #N/A — a lookup (VLOOKUP, XLOOKUP, MATCH) found no match.
  • #NUM!, #NULL!, #CALC! — invalid numbers, non-intersecting ranges, or a calculation that can’t complete.

The silent-wrong ones

Not every bad formula shows an error token. Some calculate a number that’s simply wrong. We recompute each formula with an independent engine and flag any cell where the two disagree — those are the ones worth a closer look even though Excel shows no error.

How it works

The page runs the same functions your AI agent would call through our tools: it locates every formula, confirms each result across two independent engines, and explains what it found. It reads your file in memory and never stores it — this check changes nothing, it only tells you what’s wrong.

Want this inside your AI agent, on your own machine, with no upload at all? Install xlsx-for-ai and ask Claude or Cursor to “find the broken formulas in this workbook.”