Excel and Google Sheets Formula Explainer
AI-assisted spreadsheet formula explanation. 10 free per day.
AI-assisted explanations are usually right but not guaranteed. For critical financial models, verify against the actual computed values and the function reference docs.
What this tool does
Reads an Excel or Google Sheets formula and produces a function-by-function explanation: which functions do what, what each argument is, how nested calls compose, and a notes section if the formula uses array constructs, volatile functions like NOW or INDIRECT, or other patterns with non-obvious behavior. Optional context (a one-line description of what the spreadsheet contains) lets the explanation reference your data more accurately.
How to use it
Paste the formula. Add optional context if your data has meaning the formula
alone does not communicate. Press Explain. The free tier
allows 10 explanations per IP per day. Example:
=IFERROR(VLOOKUP(A2,$D$2:$E$100,2,FALSE),"not found") returns
a clear walkthrough of the lookup, the absolute references, and the IFERROR
fallback.
Common use cases
- Inheriting a complex spreadsheet and figuring out what its formulas do.
- Documenting a financial model so reviewers can audit each cell.
- Translating a formula written in Excel to one that works in Google Sheets (the explanation surfaces dialect differences).
- Spotting why a formula returns the wrong value (the breakdown often makes the bug obvious).
- Teaching a teammate how a formula composes by showing the explanation alongside.
Common pitfalls
- Excel vs Sheets vs LibreOffice. Most formulas work the same; some (LET, LAMBDA, ARRAYFORMULA, FILTER differences) are dialect-specific. The explanation flags vendor-specific syntax when present.
- Volatile functions. NOW, TODAY, RAND, OFFSET, INDIRECT recalculate on every change. A formula that uses them silently can wreck spreadsheet performance at scale. The explanation notes when they are in use.
- Array context. A formula that returns one cell at the top of a range may be implicitly arrayified in Sheets and Excel 365. The behavior depends on the cell context, not just the formula text.
Frequently asked questions
- Where does my formula go?
- The formula and any context you provide are sent to glunty which forwards them to Anthropic Claude. glunty does not log or store the input; Anthropic processes it for the duration of the request under their data-usage policy (no training on API inputs by default). Formula text alone usually does not contain sensitive data, but if your context field describes private business logic, treat it as a brief disclosure to a third-party API.
- Why does providing context help?
- Spreadsheets carry meaning in column letters and cell ranges. =VLOOKUP(A2,$D$2:$E$100,2,FALSE) says "look up A2 in D-E and return column 2," but without context the explainer does not know that "A is product SKU" and "D-E is the price table." A one-line description of what your data represents lets the explanation use real terminology instead of generic "value in column A."
- Excel vs Google Sheets vs LibreOffice?
- Most formulas work the same. Differences: LET and LAMBDA are Excel 365 + Google Sheets only; ARRAYFORMULA is Sheets-specific (Excel uses dynamic arrays in 365 instead); FILTER exists in both but with different argument orders; IFS is in newer Excel and Sheets. The explainer notes vendor-specific syntax when it sees it.
- Can it spot circular references or volatile-function performance issues?
- Volatile functions (NOW, TODAY, RAND, OFFSET, INDIRECT) recalculate on every change to any cell. The explainer flags these in the notes section because they often cause performance problems in large spreadsheets. Circular references require seeing the whole sheet; the explainer works from one formula and cannot detect a cycle that spans cells it does not see.
- Why 10 per day instead of 5 like the other explainers?
- Spreadsheet formulas tend to be shorter than code or SQL queries. Each call costs less, so the cap can be more generous without changing the underlying budget. Heavy spreadsheet auditors who need higher volume can hit the Claude API directly for a few cents.
- Will it translate Excel formulas to Google Sheets equivalents?
- Indirectly. Pasting an Excel formula and reading the explanation surfaces what the formula needs to do; you can then look up the Sheets equivalent for any function not available there. Direct translation (paste Excel, get Sheets) is on the roadmap but not here yet. For now, the explanation is the bridge.
Cite this tool
For academic, journalistic, or technical references. Pick a format:
Citations use 2026 as the publication year. Access date is left as a fillable placeholder where the citation style expects one.