Turn CSV or Markdown tables into safer Excel files.
Import, inspect column types, and save a real `.xlsx` in this browser. Leading zeros, long identifiers, and Japanese text stay intact by default.
Import a table
The file is read locally. Nothing is processed automatically.
Review sheets, columns, and formula caches, then save only selected columns as CSV.
Text is the default. Choose only columns that you have checked as safe numbers. Limits: 5 MiB / 10,000 rows / 100 columns / 500,000 cells.
Recipient column contract (optional)
Save or load an explicit JSON contract. Inspecting the next table reuses its column order, types, required fields, blank policy, and allowed values.
Result received from the previous tool
Enter a table, then inspect it.
Safe .xlsx inspection
Choose an .xlsx workbook.
Load the contract to check required fields, blanks, types, and allowed values before saving CSV.
Sheets
Output columns
CSV preview
Excel file is ready
Package only the delivery-folder changes
Compare a previous and current folder locally, review changed and added files, and save only selected files as a ZIP. Removed, hidden, empty, and unsafe paths stop the review.
Choose the previous and current delivery folders.
Review changed and added files
Checks that protect values
- Columns are text by default. Values such as 00123, 16+ digit IDs, and date-like text are not guessed into numbers.
- Formula-looking cells are warned about and never generated as spreadsheet formulas.
- The output is one local worksheet. Input, result, and file name are not sent or stored.
After saving, confirm values and display in Excel or the system that receives the file.