SheetBrain is the spreadsheet health tool for Google Sheets. It scans your sheet in one click for the four bugs that silently break reports: broken references, mixed data types in a column, duplicate lookup keys, and schema drift (when a column moves or gets renamed and your formulas quietly point at the wrong data).
The scan is deterministic — no AI guesswork, no quota. Free and unlimited. Type =SHEETBRAIN_HEALTH() in any cell to get a health score directly in the formula bar.
Also generates formulas from plain English, explains existing formulas, and debugs #REF!/#N/A errors using the actual context of your sheet (column headers, data types, sample rows). Unlike tools that require you to bring your own OpenAI or Anthropic key, all AI is included at a flat $9/mo for 1,000 calls. No API keys. No token charges. Works on any Google account including free Gmail.
Install free on the Google Workspace Marketplace.
