Help shape the future of JSON Workbench! We'd love to hear how you use it.

Large Excel Compare & Diff Tool

Excel Compare is a secure, local-first utility to compare two large spreadsheet files (.xlsx or .xls) side-by-side. Choose specific columns, select positional or key column row matching, and export colored diffs instantly in your browser.

How It Works

Compare two Excel sheets in three easy steps

1. Upload Files

Drag and drop your spreadsheet files (.xlsx or .xls) into the dropzones. They are loaded and parsed locally.

2. Adjust Settings

Toggle specific columns to include or ignore. Choose between positional (row-by-row) or key-based column matching.

3. Export Diffs

Review highlighted modifications instantly, filter out unchanged rows, and download a color-coded Excel diff.

Powerful Comparison Features

Multi-Sheet

Supports workbooks with multiple sheets. Swap sheets independently to compare specific tabs.

Column Filters

Ignore insignificant metadata columns (like updatedAt) and focus only on the fields you want.

Key-Based Matching

Identify added/deleted rows automatically by matching against unique keys (like user ID or SKU).

Privacy Worker

Uses high-performance Web Workers to parse files locally. Sensitive details never leave your browser.

Frequently Asked Questions

Q:Is my Excel data sent to any server?

No. Like all tools on JSON Workbench, all spreadsheet parsing, diffing, and formatting run locally in your web browser. Zero bytes are uploaded.

Q:What file formats are supported?

We support Excel spreadsheet files with .xlsx and .xls extensions.

Q:Can this tool handle large Excel files?

Yes. While standard tools crash or freeze when parsing large sheets, this tool is powered by background Web Workers, allowing you to parse and compare large Excel files up to 50MB smoothly without locking up your browser.

Best Practices for Sheet Audits

To get the most accurate differences when comparing Excel files:

  • Use Unique Key ColumnsAlways select a unique key column (like an email or database ID) if rows might have been inserted or deleted. This avoids cascading modification flags.
  • Exclude Calculated ColumnsUnselect auto-generated timestamp columns to prevent them from showing false modifications on every row.
  • Verify Sheet AlignmentEnsure sheets with matching data structures are selected in both tabs when doing comparisons.