Paste an array of objects or rows and create a spreadsheet locally in your browser.
Audit JSON before Excel export with nested-field flattening, column coverage, type checks and spreadsheet formula-injection warnings.
The fast XLSX export above remains first. This optional workspace reads the same JSON, lets you choose how nested data is mapped, protects formula-like text when requested, previews the exact table, and hands the result back to the existing WTA35.rowsToXLSX() workbook writer.
Nothing is uploaded; the source remains in this browser tab.
CSV has no universal schema or type system. Delimiter detection and type summaries are practical heuristics, while repairs create a new copy instead of silently altering the source. Excel conversion focuses on cell values and simple worksheets rather than promising perfect preservation of formulas, macros, charts, external links, formatting or every workbook feature.
Use the tool first, then apply these checks to verify the inputs, interpret the result, and hand it off without displacing the primary workflow.
Nested objects and arrays do not map to one spreadsheet cell structure automatically. Decide whether to flatten object paths into dotted columns, keep nested values as JSON text, or choose a specific record array. Preserve that policy with the workbook so another user understands how the shape changed.
Untrusted strings beginning with characters such as =, +, - or @ can be interpreted specially by spreadsheet software in some workflows. When exporting external data, use a text-protection option and spot-check those cells before sharing the workbook.
Long account IDs, ZIP codes, SKUs and values with leading zeros can be damaged if a spreadsheet guesses a numeric type. Inspect a representative sample and keep identifier-like values as text when numeric arithmetic is not intended.
Before replacing the JSON source, compare record count, column count, several nested fields, nulls, Unicode text and edge-case values in the downloaded workbook. A successful download proves file creation, not that every business rule was mapped the way you intended.
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