GKrellM
GKrellM is a free system-monitoring application that presents its monitors in a single-process stack.
What GKrellM is
GKrellM is a free system-monitoring application that presents its monitors in a single-process stack. Its built-in views cover CPU activity, processes, disks, network interfaces, memory, swap, filesystems, sensors, mailboxes, battery, uptime, and a clock and calendar. Charts can scale automatically or use fixed values, while sensor and battery monitors can show configurable alarms and warnings. Themes can match a window manager, GTK, or another theme. GKrellM and its gkrellmd server accept plugins for specialized monitoring; community examples include wireless monitoring, audio control, and SNMP variables. The Internet monitor shows current TCP port connections and charts past port hits for over two days. The mailbox monitor checks mbox, maildir, MH, POP3, and IMAP. The maker lists builds for Linux, FreeBSD, Mac OS X, NetBSD, and OpenBSD, and links to a Windows version and installer. The application requires GTK 2.0, GDK 2.0, and GLib 2.0; gkrellmd can run without GTK or X libraries. Linux sensor readings may depend on hardware, kernel support, and additional software.
Good
- Free software under the GNU General Public License
- Monitors CPU, memory, disks, network, and more
- Supports themes and community plugins
- Mailbox monitor checks several mailbox formats and protocols
- Remote monitoring is supported
Watch out
- The application requires GTK 2.0, GDK 2.0, and GLib 2.0
- Linux sensor readings can require hardware support and extra software
- The latest listed release is gkrellm-2.3.5.tar.bz2
Who it suits
GKrellM suits users who want a free desktop monitor stack with system, network, and mailbox views. It may also suit people who want themes or community plugins, provided their platform and sensor requirements are met.
Verdict
GKrellM brings a broad set of system monitors into one themed stack and supports plugins, remote monitoring, and several operating systems. Check the stated library requirements and Linux sensor dependencies against your setup before choosing it.
Plans and prices
From GKrellM's own pricing page, checked 3 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Free software | Free | GNU General Public License |
The facts
Each one read from GKrellM's own pages, with the date it was checked.
What it does
- Charts and alarms
- Charts support automatic or fixed scaling, and sensor and battery monitors can use configurable alarms and warnings.checked 3 Oct 2026
- Custom sensor support
- Yeschecked 21 Sep 2026
- Latest listed release
- The official page identifies gkrellm-2.3.5.tar.bz2 as the latest release tarball.checked 3 Oct 2026
- Mail support
- The built-in mailbox monitor checks mbox, maildir, MH, POP3, and IMAP mailboxes and can launch configured mail-related commands.checked 3 Oct 2026
- Networking monitor
- The built-in Internet monitor displays current TCP port connections and charts historical port hits for over two days.checked 3 Oct 2026
- Plugins
- Both GKrellM and gkrellmd support plugins for special-interest monitors; the maker lists community plugins for functions including wireless monitoring, audio control, and SNMP variables.checked 3 Oct 2026
- Purpose
- GKrellM is a single-process stack of system monitors that supports themes matching a window manager, GTK, or other theme.checked 3 Oct 2026
- Remote monitoring
- GKrellM can run as a client and collect data from a gkrellmd server on a remote machine.checked 3 Oct 2026
- Requirements
- The GKrellM application requires GTK 2.0, GDK 2.0, and GLib 2.0; the gkrellmd server requires GLib and can run without GTK or X libraries.checked 3 Oct 2026
- Security and compliance
- The official page states that GKrellM is released under the GNU General Public License and does not state a security certification or compliance standard.checked 3 Oct 2026
- Support
- The maker invites users to email Bill Wilson with questions or suggestions and links to a GKrellM mailing list.checked 3 Oct 2026
- System monitoring
- Built-in monitors include CPU, processes, disks, network interfaces, memory, swap, filesystems, sensors, mailboxes, battery, uptime, and clock/calendar.checked 3 Oct 2026
- Themes
- GKrellM supports themes, and the official page links to a theme site and theme documentation.checked 3 Oct 2026
Money
- Free plan
- Yeschecked 21 Sep 2026
Where it runs
- Linux sensor dependencies
- On Linux, temperature, fan, and voltage monitoring depends on kernel and motherboard support and may require lm_sensors, sysfs sensors, or mbmon; disk temperature and NVIDIA GPU temperature monitoring also have listed daemon or software dependencies.checked 3 Oct 2026
- Platform support
- The maker describes Linux, FreeBSD, Mac OS X, NetBSD, and OpenBSD builds, and links to a Windows version and installer.checked 3 Oct 2026
- Supported platforms
- Linux,FreeBSD,Mac OS X,NetBSD,OpenBSD,Windowschecked 21 Sep 2026
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