How to Compare Workbooks and Analyse Formula Differences Using the Inquire Add-In in Microsoft Excel

Financial analysts, auditors, and data engineers frequently manage multiple iterations of complex spreadsheets. When models undergo iterative reviews, tracking changes across hundreds of interdependent cells manually is error-prone and time-consuming. While standard cell highlighting or conditional formatting detects basic visual discrepancies, it cannot expose underlying formula alterations, structural modifications, or circular dependencies. Microsoft Excel includes an enterprise-grade auditing extension known as the Inquire add-in. Available in Excel for Microsoft 365 and Office Professional Plus, Inquire provides automated workbook comparisons, visual relationship diagrams, and detailed modification exports.

Verifying System Requirements and Enabling the Inquire Add-In

The Inquire extension is built directly into Microsoft Excel but remains deactivated by default. Because it operates as a COM add-in, you must enable it through Excel’s options console.

Step 1: Accessing COM Add-Ins

1. Launch Microsoft Excel on your computer.
2. Click File in the top-left corner and select Options from the bottom of the navigation menu.
3. In the Excel Options dialogue, click the Add-ins tab in the left sidebar.
4. Locate the Manage dropdown at the bottom of the window, change the selection from Excel Add-ins to COM Add-ins, and click Go.

Step 2: Activating the Inquire Feature

1. In the COM Add-ins list, check the box adjacent to Inquire.
2. Click OK to confirm.
3. A new dedicated Inquire tab will appear in the primary Excel ribbon interface between Data and View (or next to Help).

Comparing Two Workbooks Side by Side

The flagship capability of the Inquire add-in is the Compare Files tool, which evaluates two versions of a spreadsheet down to individual cell definitions.

Step 1: Launching the Comparison

1. Open both versions of the spreadsheet in Excel (e.g., Budget_Q3_V1.xlsx and Budget_Q3_V2.xlsx).
2. Navigate to the Inquire tab on the ribbon and click Compare Files in the Report group.
3. In the Compare Files dialogue box:
   • Under Compare: select the original base workbook.
   • Under To: select the revised target workbook.
4. Click Compare to execute the analysis.

Step 2: Analysing Visual Differences

Excel opens an interactive comparison pane divided into dual viewports:

• The top-left panel displays the original worksheet, while the top-right displays the updated version.
• Discrepancies are colour-coded according to the category legend displayed along the bottom left:
  • Formulas: Marked with purple highlighting to show modified calculations.
  • Entered Values: Marked with green highlighting to show altered numerical or text inputs.
  • Calculated Values: Highlighted in cyan to show downstream changes triggered by upstream modifications.
  • Structural / Blank Cells: Highlighted in red or yellow indicating added or deleted rows and columns.
• Clicking any entry in the lower details table automatically snaps both workbook viewports directly to the affected cell coordinates.

Step 3: Exporting the Discrepancy Log

To provide documentation for compliance or team review, click the Export Results button in the comparison toolbar. Excel creates a consolidated audit spreadsheet listing Sheet Name, Cell Coordinate, Difference Type, Old Value/Formula, and New Value/Formula.

Generating Comprehensive Workbook Analysis Reports

Beyond file comparisons, Inquire provides single-workbook structural diagnostics via the Workbook Analysis tool:

1. Click Workbook Analysis in the Inquire ribbon.
2. Select items to evaluate, including Visible and Hidden Sheets, Formulas with Errors, Formulas with Inconsistent Syntax, and External Links.
3. Click Excel Export to produce a formal health report detailing hidden worksheets, unused named ranges, and high-risk formulas.

Visualising Cell and Worksheet Relationships

Auditing nested calculation chains is significantly easier with Inquire’s interactive architectural diagrams:

• Cell Relationship: Visualises how specific input cells cascade into downstream summary outputs.
• Worksheet Relationship: Maps data flows across disparate sheets within the same workbook.
• Workbook Relationship: Diagrams dependencies between external workbooks, databases, and remote file links.

By incorporating the Inquire add-in into your spreadsheet workflow, you eliminate manual auditing errors and ensure complete structural integrity across financial and analytical models.