How to Find Missing Rows Between Two Files

You have two files. They should contain the same records — but do they? Finding missing rows is one of the most common data tasks, whether you're checking a data migration, auditing a report, or reconciling accounts.

The manual way (and why it's painful)

The classic approach in Excel:

Add a VLOOKUP in File A that looks up each ID in File B
Filter for #N/A results — those are the missing rows
Repeat in the other direction (File B looking up in File A)
Combine the results

This works for small files. But it's slow, error-prone, and gets complicated when your key spans multiple columns (e.g., matching on both name and date).

The fast way

Upload both files to SheetPair. Set your key columns. In seconds, you get:

Only in File A — rows that exist in File A but not in File B
Only in File B — rows that exist in File B but not in File A
Plus matched rows and rows with differences, if you want the full picture

You can export just the missing rows as CSV or Excel with one click.

Common use cases

Data migration verification

After migrating records from one system to another, export both and compare. Missing rows = records that didn't transfer.

Report auditing

Got two reports that should show the same transactions? Upload both and instantly see which records are missing from each.

List deduplication

Have a master list and a new import? Find which records from the import are already in your master list and which are new.

Vendor reconciliation

Compare your purchase orders against vendor invoices to find orders that haven't been invoiced yet (or invoices without matching POs).

Multi-column keys

Sometimes a single column isn't enough to uniquely identify a row. For example, you might need to match on both Customer Name AND Invoice Date together.

SheetPair supports multiple key columns — just mark each one as a "key" in the column mapper. Rows must match on ALL key columns to be considered a match.

What about duplicates?

If File A has two rows with the same key, and File B has one, SheetPair matches them correctly and surfaces the extra row. No formula gymnastics needed.

Get started

Drop your two files at sheetpair.com and filter by "Only in File A" or "Only in File B" to see exactly what's missing. Free for files up to 1,000 rows.