duf — Disk Usage/Free Utility Made Beautiful

Introduction

df is one of those classic Unix tools that does its job but rarely surprises you with clear output. duf is the modern replacement: same information, but as a colorized table with sensible defaults, categorized mounts (local / network / special), and units humans actually read.

With over 14,000 GitHub stars, duf is the "install once, alias df" kind of tool that quietly makes your shell nicer. Written in Go, it's a single binary, cross-platform, and starts instantly.

What duf Does

duf enumerates mount points (the same way df does) and prints them in three categorized tables: local (real filesystems), network (NFS, SMB, SSH mounts), and special (tmpfs, overlayfs, proc). Each shows size, used %, available, mount point, filesystem type — with colored bars for used percentage.

Architecture Overview

[duf (Go binary)]
      |
[Read mount table]
   /proc/mounts (Linux), getmntinfo (BSD/macOS), Win32 API
      |
[statfs() per mount]
   total, free, avail, inodes
      |
[Categorize]
   local / network / special
      |
[Render table]
   UTF-8 box drawing + color (respecting NO_COLOR)

Self-Hosting & Configuration

# Output in various formats
duf --output mountpoint,size,used,avail,usage  # choose columns
duf --json                                     # JSON for scripting
duf --theme dark                               # force theme (auto/dark/light)
duf --width 160                                # wrap at custom width
duf /home /var                                 # only show these paths

# Filter by filesystem type
duf --only-fs ext4,zfs
duf --hide-fs squashfs,tmpfs,devtmpfs

# Sort
duf --sort size
duf --sort usage

# In scripts: JSON output
duf --json | jq '.[] | select(.usage > 0.9)'

# Drop-in replace df in aliases
alias df='duf'
# For compatibility, you can also keep df available:
alias df='/usr/bin/df'    # real df
alias df2='duf'            # pretty df

Key Features

• Categorized tables — local / network / special separated for clarity
• Colorized usage bar — green/yellow/red based on thresholds
• UTF-8 box drawing — clean tables that look great in modern terminals
• JSON output — script-friendly structured data
• Column customization — pick exactly which columns to show
• Sort + filter — by size, usage, filesystem type, mount point
• Cross-platform — Linux, macOS, Windows, BSD
• Theme detection — auto-picks light/dark palette

Comparison with Similar Tools

FAQ

Q: duf vs dysk? A: Both are df replacements. duf prints a clean static table; dysk (formerly lfs) has an interactive TUI mode for browsing. Many users install both — duf for scripts, dysk for exploration.

Q: Does it work on network mounts? A: Yes — NFS/SMB/SSH mounts appear in the "network" category with proper size accounting. For slow mounts, duf may take a moment per entry (it calls statfs).

Q: Can I use it in shell scripts? A: Yes — duf --json outputs machine-readable data. For just-a-number output, plain df is still simpler; use duf when you want readable human output in dashboards, reports, or MOTD.

Q: Does it show inode usage? A: Yes — add --inodes or --output inodes_usage. Essential on filesystems where tiny files can exhaust inodes before bytes.

Sources

• GitHub: https://github.com/muesli/duf
• License: MIT