Guide

Compare Excel Files Online

Two versions of the same report, two exports a week apart — and you need to know exactly what changed. Here are three reliable ways to compare Excel files, from a quick visual check to a repeatable, formula-driven diff.

1. Quick visual check: View Side by Side

For small sheets, open both files and use View → View Side by Side with synchronous scrolling. It costs nothing to set up, but it depends on your eyes — fine for a dozen rows, risky for a thousand.

2. Cell-level diff with a formula

If both files share the same layout, add a comparison sheet and fill it with =IF(A1<>[Book2]Sheet1!A1,"DIFF",""). Every mismatched cell lights up, and you can filter or count the DIFF flags. This is the fastest way to answer “did anything change?” across a whole grid.

3. Row matching across files with VLOOKUP or COUNTIF

When rows can move around, compare on a key column (an ID, an email, an order number) instead of by position. =COUNTIF(other!A:A,A2)=0 marks rows that exist in one file but not the other; VLOOKUP or XLOOKUP pulls the matching value over so you can compare amounts, dates, or statuses side by side.

Doing this in the browser

The same key-column approach works in TableDI, an online data table: load both sheets and use the formula panel — including VLOOKUP and COUNTIF — to match rows and flag differences without leaving the browser. The TableDI docs cover each formula the panel supports.

Which method should you use?

  • Same layout, quick answer — the cell-level IF formula.
  • Rows move around — match on a key column with VLOOKUP or COUNTIF.
  • No desktop Excel at hand — an online table with a formula panel.

FAQ

How do I compare two Excel files for differences?

Open both workbooks and use View → View Side by Side for a quick visual check. For a cell-level report, add a formula like =IF(A1<>Sheet2!A1,"DIFF","") in a copy of the sheet, or match rows across files with VLOOKUP or XLOOKUP on a shared key column.

Can I compare Excel files without installing anything?

Yes. Formula-based comparison works in Excel itself with no add-ins. If you prefer a browser, an online data table like TableDI lets you load both sheets and match rows with VLOOKUP or COUNTIF from its formula panel.

How do I find rows that exist in one file but not the other?

Use COUNTIF against the other file’s key column: =COUNTIF(other!A:A,A2)=0 marks rows missing from the other file. Filter on that column to list them.