Directory Structure Comparator

A Directory Structure Comparator is a tool that analyzes two sets of file listings - from pasted text, uploaded manifests, or ZIP archives - and identifies the differences between them. It works by parsing each input into a normalized map of filenames with sizes, then comparing the two maps to categorize every file as Added, Removed, Changed, or Unchanged. The results are displayed in an interactive tabbed interface with summary statistics.

The tool supports three input formats: (1) Plain text pasted directly into the textarea - one file per line, optionally with comma-separated or bracket-enclosed sizes (e.g., "file.txt,1024" or "file.txt [1024]"). (2) Uploaded text files (.txt) and comma-separated value files (.csv). (3) Uploaded ZIP archives (.zip) - these are automatically decompressed in your browser to extract the internal file structure. Lines starting with #, ;, or // are treated as comments and ignored.

The tool compares files by their name/path. If a file exists in both inputs but has a different size, it is categorized as Changed. Size comparison requires that at least one of the inputs provides size information. ZIP archives always include uncompressed sizes. For text listings, you can optionally include file sizes using comma or bracket notation. If no sizes are available, the tool will only detect Added and Removed files.

Absolutely. All processing happens entirely within your browser. Your directory listings, uploaded files (including ZIP archives), and comparison results never leave your device. No data is transmitted to any server, stored in any database, or logged by any service. When you close or refresh the page, all data is discarded. This makes the tool safe for analyzing sensitive file inventories and security audit data.

Yes. You can upload ZIP archives for either or both inputs. The tool will automatically decompress the ZIP file in your browser (using JavaScript's native archive parsing) and extract the list of stored files with their uncompressed sizes. This is particularly useful for comparing software release packages, backup archives, or any collection of files bundled into ZIP format.

Added files are present in the Target (B) listing but not in the Reference (A) listing - these are new files. Removed files are present in the Reference (A) listing but not in the Target (B) listing - these files were deleted. Changed files are present in both listings but have different sizes - their content likely changed. Unchanged files are present in both listings with the same size - these files are identical. The four categories give you a complete picture of what changed between the two states.

Since all processing happens locally in your browser, the limit depends on your device's available memory. Most modern browsers can handle ZIP archives up to several hundred megabytes. For very large archives, ensure sufficient RAM is available. The tool processes archives in chunks to minimize memory usage.

The change rate is calculated as: (Total Changed Files / Total Unique Files) × 100, where Total Changed Files includes Added, Removed, and Changed files, and Total Unique Files is the larger of the two input file counts. This percentage gives you a normalized measure of how much the directory structure changed between the two states.

Yes. The Directory Structure Comparator is an excellent tool for security incident investigation. By comparing a known-good file manifest against a current system listing, you can quickly detect unauthorized file additions (potential malware), unexpected deletions (possible data exfiltration), and changed system files (tampering). The browser-local processing ensures that sensitive evidence is never exposed to external servers.