How to Compare Two Folders on Windows (4 Free Ways)

What "Comparing Folders" Actually Means

A useful folder comparison answers four questions about two directory trees:

• What's only in folder A? (missing from B)
• What's only in folder B? (missing from A)
• Which files exist in both but differ? (same path, different contents)
• Which files are identical or duplicated?

Comparing by name and size alone answers these badly — a file can have the same size but different contents. Comparing by SHA-256 checksum answers them exactly, because the checksum is derived from the file's bytes. See how checksum-based folder verification works.

Method 1: Free Online Tool (Easiest)

No commands, no install. Our free Folder Compare tool reads both folders recursively in your browser and categorizes every file.

1. Open the Folder Compare tool.
2. Select folder A, then folder B (drag-and-drop works too).
3. Every file is hashed with SHA-256 as it loads.
4. Results group files as Only in A, Only in B, Identical, Different, and Duplicates.

Method 2: Robocopy /L (Built Into Windows)

Robocopy is included with Windows. The /L ("list only") switch makes it report what would change without copying or deleting anything — perfect for a safe, read-only comparison:

robocopy "C:\FolderA" "C:\FolderB" /L /E /NJH /NJS /FP /NDL

/E includes subfolders, and /L guarantees nothing is written. The output flags new, changed, and extra files. Robocopy compares by size and timestamp by default — fast, but less precise than a checksum for catching silent content changes.

Method 3: PowerShell Compare-Object

To compare which files exist in each folder, list both and diff them with Compare-Object:

$a = Get-ChildItem -Recurse "C:\FolderA" | ForEach-Object { $_.FullName.Replace("C:\FolderA", "") }
$b = Get-ChildItem -Recurse "C:\FolderB" | ForEach-Object { $_.FullName.Replace("C:\FolderB", "") }
Compare-Object $a $b

The arrow in the output (=> or <=) tells you which folder each file belongs to. To compare contents too, pipe each file through Get-FileHash and compare the hashes — the same technique used to find duplicate files.

Method 4: fc for Single Files

When you only need to compare two specific files (not whole folders), the classic fc command shows a line-by-line or byte-by-byte difference:

fc /b "C:\FolderA\report.pdf" "C:\FolderB\report.pdf"

/b does a binary comparison. For a friendlier, checksum-based file check, use the free Compare Files tool.

Which Method Should You Use?

Compare Before You Sync

For the full breakdown, read Folder Comparison vs Folder Sync.

Frequently Asked Questions

How do I compare two folders on Windows?

The easiest free way is a browser tool like FolderManifest Folder Compare: pick two folders and it lists which files are missing, changed, identical, or duplicated using SHA-256 checksums. Built-in options include Robocopy /L and PowerShell Compare-Object.

Does Windows have a built-in folder compare tool?

There's no graphical app, but Windows includes command-line tools: Robocopy (use /L to list differences without copying), PowerShell Compare-Object, and fc for single files.

How do I compare folders without syncing them?

Use a comparison tool, not a sync tool. Comparison is read-only and shows differences without changing either folder. Run Robocopy with /L, or use an online folder-compare tool.

Is it safe to compare folders online?

With FolderManifest, yes — files are processed in memory and discarded immediately after comparison, with no account or long-term storage. For larger or confidential jobs, the desktop app keeps everything local.

Continue Learning

• Compare Folders Online (No Installation Required) →
• Folder Comparison vs Folder Sync: What's the Difference? →
• How to Find Duplicate Files on Windows →