XLSX Formula Checker

Inspect explicitly supplied XLSX workbooks or small inline workbooks with the same bounded Rust/WASM calculation engine used by Workbook Tools. Read formulas and stored values, check reported workbook issues, calculate selected outputs, and compare changes to existing literal inputs. Stored caches and fresh calculation results are reported separately. Calls do not overwrite your original file or save edited workbooks. Formula support is partial; unsupported features and resource limits are reported rather than silently treated as Excel-compatible. The service cannot control Excel, browse local files, fetch workbook URLs, or automatically access Claude attachments. Optional AI formula help sends only the task, formula and text context you explicitly supply to OpenRouter and its selected model provider; suggestions are not executed or verified. No Workbook Tools account or user API key is needed. Read the setup page for supported inputs and limits.