Enter your data or use the example, then run the tool.
Worked example
The sample distinguishes formula cached value 5 from literal =2+2. CSV exports cached values and prefixes dangerous strings with an apostrophe.
Method
ExcelJS reads actual XLSX after ZIP/XML preflight. Types, formulas and cached values stay distinct. No formulas, macros, links or external connections run. CSV is quoted UTF-8 with BOM and formula-injection escaping.
Limits
XLSX ≤5 MiB / 20 sheets; selected sheet ≤1,000 rows / 50 columns, source worksheet XML ≤50,000 stored cells. Table previews 500 cells; CSV exports the full bounded selected sheet. Cached values may be stale/missing; no calculation engine or layout, XLS/password support. Worker limit 15 seconds.
All processing stays in the browser. Workers terminate at the stated deadline or cancellation. No input/logs are sent to analytics.
Office ZIP ≤2,000 entries; actual expanded data ≤32 MiB and ≤100× input, each XML ≤8 MiB. DTD/entities and traversal paths are rejected before conversion.
Your inputs stay on this device. Only optional, consented page visits are measured. Input values, files, filenames and processing logs are not sent to Analytics.
When switching languages, text, settings and selected files are temporarily kept on this device. Transfers are removed after restoring; interrupted transfers are cleaned up on a later visit. Inputs and files are never uploaded.