htop

htop is an interactive, text-mode process viewer for people who work in terminals. It is best suited to Linux and macOS users who want process visibility and a few direct controls without leaving the command line. Its adaptable display and free distribution make it a practical choice, but it cannot show reliable swap use for each process.

Overview

Running in console or X terminals with ncurses, htop presents processes in an interactive terminal interface rather than a graphical dashboard. That makes it a natural fit for command-line workflows, including on systems where a terminal is the preferred way to inspect running workloads. The project dates to 2004 and is distributed as source code and as pre-compiled binaries from operating-system distributions.

Package installation examples cover Debian, Fedora, Gentoo and Arch Linux; macOS users can install htop through Homebrew. Its memory meter needs some interpretation: the percentage reflects memory used by processes, while Linux also uses available memory for buffers and disk cache. Users looking for exact per-process swap accounting should choose another tool, since htop does not provide that column and cannot reliably determine exact swap use, including for shared pages.

Key features

Readable and adjustable terminal display

Unicode Braille-character graphs and a Unicode tree view bring visual structure to a text interface. The tree view helps make process relationships legible, while support for large processor counts makes htop relevant on high-core-count machines. Users can choose color themes for dark or light terminals and customize header meters, which is useful for adapting the display to a preferred setup.

Process controls

htop can configure I/O scheduling priority and CPU affinity. Those controls make it more than a passive process viewer for users who need to adjust how a process is scheduled. Its scope remains terminal-based process viewing and control, rather than a broad graphical monitoring interface.

Pricing

htop is free: the Free plan costs nothing and includes freely available source code and distribution binaries. There is no paid tier to weigh against a restricted free edition, and no free trial is offered. It is a straightforward fit for individuals and organizations seeking a no-cost terminal process viewer; the trade-off is the product's focused feature set, not a tier cap.

Platforms

htop's current releases support Linux, FreeBSD, NetBSD, OpenBSD, DragonFly BSD, macOS and Solaris. The listed platform coverage centers on Linux and macOS, with the project's supported-system range extending to several BSD systems and Solaris. The terminal and ncurses requirements make it most appropriate for users already working in a compatible text environment.

Who it's for

Choose htop if you want a free, interactive process view in a terminal, value a customizable display, or need to configure I/O priority and CPU affinity. Its support for large processor counts is useful when a system has many cores to represent. It is a weaker fit for users who need per-process swap figures or prefer a web-based or graphical monitoring interface.

Pros and cons

• Pro: Free source code and distribution binaries make it accessible without a paid plan.
• Pro: Customizable header meters and dark- and light-terminal themes let users tune the display to their terminal.
• Pro: I/O scheduling priority and CPU affinity controls add practical process management to the viewer.
• Con: There is no per-process SWAP column, so htop cannot answer which process is using swap.
• Con: The memory meter's process-use percentage does not capture the whole Linux memory picture because buffers and disk cache also use available memory.
• Con: A terminal interface requiring ncurses is not a fit for readers seeking a graphical or web dashboard.

Alternatives

Glances is another free option for readers who want a monitoring tool spanning platforms including Android, web and Windows; optional features require extra dependencies. Choose PM2 instead when process management with a real-time web interface is the priority: its Runtime plan is free, while Plus is $79 a month.

bottom (btm) is a free alternative for readers considering a Linux, macOS or Windows option. btop is a free resource monitor for Linux and macOS, and is a reasonable alternative for users seeking that category of tool. Monit is free open-source software for Linux, macOS and self-hosted use. OpenProcMon is the Windows-only choice; it is 64-bit Windows software, and live capture requires Administrator privileges.

Process Lasso is for Windows users who want a process-management option with free and paid plans; its Single PC Monthly plan costs $4.95 a month, billed as a recurring subscription, cancelable at any time, for one PC. runit is a free option for Linux, macOS and self-hosted use.

For more options, browse Process Monitoring Software or System Information Software.

Verdict

Choose htop if you want a free, configurable terminal process viewer with CPU-affinity and I/O-priority controls across Linux and macOS, alongside support for several BSD systems and Solaris. Its main reason to choose it is the useful combination of terminal visibility and process controls at no cost. Look elsewhere if exact per-process swap use is essential or you need a graphical monitoring experience.