Folder Diff -
Compare Two Folders & Directories Online

A Merged Tree That Shows Only What Changed

Most folder compare tools show two separate lists and ask you to scan both. This one merges both directory trees into a single view, interleaving files by path so added, removed, and modified entries sit exactly where they belong in the hierarchy. Unchanged files are hidden by default — toggle them back if you need the full picture — so the tree stays focused on differences even in projects with thousands of files. Each entry carries a coloured status badge and, for modified files, a size delta so you can spot a ballooned asset or an unexpectedly shrunk config without clicking into it.

Three Categories Of Change

Every file lands in exactly one bucket. Identical files stay hidden so the view remains focused, and each category gets its own colour and icon — scannable at a glance even in a tree with hundreds of entries.

How To Compare Two Folders Online

Four steps and you're looking at every difference. No sign-up, no download, no waiting on a server — just a browser and the two directories you want to diff.

1. 01Pick The First Folder. Click the left panel to open a native folder picker (Chrome, Edge, Brave, Arc) or drag a directory straight from your file manager. Firefox and Safari don't support the File System Access API yet, but drag-and-drop works just as well — the scan starts the moment you release.
2. 02Pick The Second Folder. Same action on the right. Both directories are walked recursively in the background — sub-folders, nested packages, deep asset trees — with commonly ignored paths like node_modules and .git automatically excluded. You'll see early results while the scan is still running on large trees.
3. 03Review The Merged Tree. Every file appears once, colour-coded by status. Collapse sub-folders you don't care about, type into the search field to filter by filename or path, or click the status chips at the top to show only additions, only removals, or only modifications. Keyboard shortcuts (j/k or arrow keys) let you walk the list without touching the mouse.
4. 04Drill Into Modified Files. Click any text file to open its full diff. Split view places both versions side by side; unified view interleaves them in a single column. Character-level highlights pinpoint the exact token that changed, and the diff computes in a background Web Worker so the UI stays responsive even on large files. Binary files show a size comparison instead.

Why This Folder Compare Tool Stands Out

A free, browser-based directory compare utility with the depth of a desktop app. These are the capabilities that matter when you're comparing real projects — not toy demos.

1. 01Full Recursive Scanning. Both directories are walked to any depth. Deeply nested source trees, monorepo structures with dozens of packages, asset folders five levels deep — everything lands in the merged tree regardless of nesting, so you compare all files in two directories without worrying about what's hidden inside sub-folders.
2. 02Intelligent Ignore List. Paths like node_modules, .git, dist, build, __pycache__, and .DS_Store are excluded automatically so the tree shows real project files, not tooling noise. Hidden dotfiles are toggled separately, giving you control over whether .env, .eslintrc, and similar configs appear.
3. 03Built-In Line-By-Line Diff. Click any modified text file and a full diff appears in the side panel — split or unified, character-level highlights, context-collapsed unchanged regions. It's the same quality you'd expect from a standalone diff checker, but you don't leave the folder view to use it.
4. 04SHA-256 Content Hashing. When two files have the same size, a content hash determines whether they're truly identical or subtly different. This catches single-character edits that size alone would miss, without reading the full file into the diff engine unnecessarily.
5. 05Background Web Worker. File diffs are computed off the main thread so the tree stays scrollable and the UI never freezes, even when you click into a large file with thousands of lines of changes.
6. 06100% Private And Client-Side. Your folders are read from disk by the browser with your explicit permission. Nothing is uploaded anywhere — no server, no database, no analytics on your file contents. The comparison is forgotten the instant you close the tab. Safe for proprietary source, internal configs, and anything you'd never paste into a cloud tool.
7. 07No Installation. No software to download, no package to install, no PATH to configure. Open the page in any modern browser and start comparing. Works on macOS, Windows, Linux, and ChromeOS — the same tool everywhere, with zero setup.

What People Use It For

Any time you have two directories and need to know what differs between them. These are the real-world scenarios that bring people here most often.

Works On Every Operating System

No platform-specific software to install. The same browser-based tool replaces the scattered OS-specific utilities people have been using — FileMerge on Mac, WinMerge on Windows, meld on Linux — with a single tool that works identically everywhere.

Browser Support

Chrome, Edge, Brave, and Arc get the fastest experience via the File System Access API — a native folder picker opens directly to your filesystem, and file handles let the tool read content on demand without loading everything into memory upfront. Firefox and Safari don't support this API yet, so they fall back to drag-and-drop, which works reliably but requires an extra gesture and is slightly slower on very large trees because all file metadata must be read at drop time.

Compare Directories And Folder Contents Online

Whether you call them folders or directories, the comparison works the same way: both trees are walked recursively, every file is matched by its relative path, and differences are surfaced in a single merged view. Use it as a directory compare tool on any platform — Mac, Windows, Linux, ChromeOS — without installing software to compare files and folders. It replaces diff -r output, meld windows, WinMerge sessions, and Beyond Compare licenses with a single browser tab that works everywhere and costs nothing.

The merged tree tells you what changed at a glance — added files in green, removed in red, modified in amber, each with a size delta — and clicking into any modified file opens a full line-by-line diff with character-level precision. That's what separates this from running a command that lists filenames: you get the why, not just the what. It's the fastest way to compare folder contents after a migration, verify a backup, audit a deployment, or diff two directories after a refactor, and because everything runs client-side your files never leave your device.

Frequently Asked Questions