How to Redact an Excel Spreadsheet

Overview

Spreadsheets present unique redaction challenges: sensitive data can appear in cell values, formulas, named ranges, hidden sheets, and comments. Conseal's Excel redaction covers all of these surfaces, producing a clean .xlsx file where sensitive columns or rows are replaced with placeholder values while preserving the spreadsheet's structure and formulas for AI analysis.

Step-by-step instructions

Follow these steps to redact sensitive data from an Excel spreadsheet using Conseal.

1. 1

   Open your spreadsheet in Conseal

   Launch Conseal and open your .xlsx file. Conseal renders all sheets and detects hidden sheets, merged cells, and named ranges.

2. 2

   Select columns or cells to redact

   Click on column headers to redact entire columns, or select individual cells or ranges. For large spreadsheets, use the 'Detect PII Columns' button — Conseal will identify columns containing names, IDs, emails, or financial data.

3. 3

   Choose a redaction mode

   Select 'Replace with placeholder' to substitute values with generic tokens (e.g. [NAME_1], [EMAIL_1]), or 'Replace with synthetic data' to fill cells with realistic but fake values that preserve column data types for AI analysis.

4. 4

   Apply redactions

   Click 'Apply Redactions'. Conseal processes all sheets, replaces selected values, strips comments containing sensitive data, and removes personal metadata from the file properties.

5. 5

   Verify and export

   Review the redacted spreadsheet preview. Confirm formulas referencing redacted cells still resolve correctly. Click 'Export' to save the redacted .xlsx file, ready for upload to any AI tool.