Formula inspector

Paste a formula. Get four kinds of feedback.

An explanation in plain English, a lint check for anti-patterns, a pretty-printed version, and a complexity score. All four run client-side, instantly, no API calls.

Tip: press Ctrl+K from anywhere to focus the input.
Sample 1: VLOOKUP + IFERROR Sample 2: Nested IF Sample 3: Volatile OFFSET Sample 4: Clean LET
What gets checked

The lint rules

  • Volatile functions — NOW, TODAY, RAND, RANDBETWEEN, OFFSET, INDIRECT, CELL, INFO. Recalculate on every workbook change.
  • Legacy with modern alternative — VLOOKUP/HLOOKUP (use XLOOKUP), CONCATENATE (use TEXTJOIN/CONCAT).
  • Deeply nested IFs — three or more flagged; suggest IFS instead.
  • VLOOKUP with hardcoded column index — fragile under column inserts.
  • Outer IFERROR — hides every error type including bugs; suggests IFNA where applicable.