ncdu, TreeSize, WinDirStat, DaisyDisk, SpaceSniffer, Baobab Disk Usage Analyzer, GrandPerspective, KDirStat, SpaceMonger, WhatSize, OmniDiskSweeper, Disk Inventory X, SequoiaView, DiskUsage, crossdirstat, Grid Size File Manager, DiskSavvy, JDiskReport, Filelight, Xinorbis, Large Files Finder, HDGraph, FSV, FolderSizes, Disk Space Fan, Overdisk, Disktective, Directory Report, Advanced Disk Space Monitor, xdiskusage, GraphVu Disk Space Analyzer, DiskWave, Space Radar, FatFileFinder, Disk Xray, Disk Usage Reports, Directory Size Calculator, FilePro, TreePie, Total Directory Report, SquirrelDisk, K4DirStat, WinExt Free, RidNacs, i.Disk, TDP x-Ray, 1Tree Pro, DirGraph, SpaceObServer, GetFolderSize, WinFrigate, Disk Space Visualizer, DiskMapper, Disk Space Fan Pro, ClearDisk, Disk Space Pro, DiskTriage, StepTree, GD Map, Disk Space Finder, UtilStudio Disk Space Finder are some alternatives to WizTree.