Duplicate File Detection and Storage Organization Tool

Overview #Personal Development

A web-based business efficiency tool for analyzing large volumes of files accumulated on your computer and organizing duplicates and unnecessary files. With a Local-first design where all processing is completed within the browser, file contents are never sent to a server.

Main Features

• Complete Duplicate Detection: Reliable duplicate identification using SHA-256 hashing. Comparison is based on content, not file names
• Folder Selection and Recursive Reading: Analyzes all files under a selected folder using the File System Access API
• Metadata Analysis: Displays file size, modification date, file extension, and relative path
• Same Name / Similar Name Detection: Separates and displays files with identical or similar names as candidates
• Storage Capacity Analysis: Automatically calculates storage breakdown by file extension, folder, and size range
• Human Review: Explicitly judge detected results as "keep" or "organize candidate"
• Safe Plan Output: Does not delete actual files; outputs organization plans in CSV and JSON formats
• Large / Old / Empty Detection: Automatically classifies large files, old files, and empty files
• Demo Feature: Try the entire workflow with 40 fictional files even without actual files

Characteristics

• Complete processing within the browser. File contents and hash values are never sent to a server
• Automatically calculates reducible capacity and number of redundant copies
• Large files are read in 4 MiB chunks, prioritizing memory efficiency
• Fast hash calculation with Web Worker (runs on main thread in unsupported environments)
• Safe design that stops at the planning stage without deleting or moving actual files

Useful For

• Those who want to organize their computer storage but are unsure what to delete
• Those with many duplicate files and want to confirm which ones to keep
• Those who want detailed information about storage capacity breakdown
• Those who want to organize unnecessary files before cloud or backup synchronization