ncdu, TreeSize, DaisyDisk, WizTree, SpaceSniffer, Baobab Disk Usage Analyzer, GrandPerspective, KDirStat, SpaceMonger, WhatSize, OmniDiskSweeper, Disk Inventory X, Folder Size Explorer, SequoiaView, DiskUsage, crossdirstat, Grid Size File Manager, DiskSavvy, JDiskReport, Filelight, Xinorbis, DiskView, HDGraph, QDirStat, FSV, FolderSizes, Disk Space Fan, Overdisk, Disktective, Directory Report, xdiskusage, GraphVu Disk Space Analyzer, DiskWave, Space Radar, Disk Xray, Disk Usage Reports, Directory Size Calculator, IntoDisk, FilePro, TreePie, Total Directory Report, SquirrelDisk, K4DirStat, RidNacs, i.Disk, TDP x-Ray, 1Tree Pro, DirGraph, SpaceObServer, GetFolderSize, WinFrigate, Disk Space Visualizer, DiskMapper, PA Storage Monitor, Disk Space Fan Pro, ClearDisk, Philesight, diskring, xdu, Disk Space Pro, Puran Disk Files, WindowsTree, DiskTriage, FoldersReport, StepTree, GD Map, Disk Space Finder, Purple Tree, FTPpie, UtilStudio Disk Space Finder are some alternatives to WinDirStat.