Free Process Viewer: Top Tools to Monitor Windows & macOS ProcessesMonitoring running processes is essential for troubleshooting performance problems, finding resource-hungry apps, detecting suspicious behavior, and keeping your system responsive. This guide covers what a process viewer does, key features to look for, and the best free tools for Windows and macOS — with tips on how to use them safely.
What is a process viewer?
A process viewer is a utility that lists active processes and associated information (CPU, memory, disk and network usage, threads, open handles, start time, and more). Unlike simple task managers, advanced process viewers provide deeper diagnostics: process trees, real-time graphs, I/O statistics, module/driver listings, and options to inspect or suspend individual threads.
Why use a dedicated process viewer?
- Diagnose CPU or memory spikes.
- Find background apps slowing startup or draining battery.
- Identify malware or unwanted background processes.
- Inspect which files and network connections a process uses.
- Dump or analyze process memory for debugging.
Key features to look for
- Real-time CPU, memory, disk I/O, and network usage.
- Process tree and parent/child relationships.
- Detailed process properties: command line, loaded modules, environment.
- Ability to suspend/terminate processes and change priorities.
- Search and filtering by name, PID, or resource use.
- Logging, snapshots, and historical charts.
- Low overhead — lightweight monitoring without adding load.
- Portability or installer options.
- Security: signed binaries, active community, or open source.
Best free process viewers for Windows
1) Process Explorer (Microsoft Sysinternals)
Why it stands out:
- Powerful, free, and widely trusted by sysadmins.
- Shows detailed process trees, handles, loaded DLLs, GPU usage, and process properties. Key features:
- Real-time graphs and per-process resource usage.
- Search for handles or DLLs.
- Verify digital signatures and check publisher info. How to use (quick):
- Run as admin for full info. Hover a column for help, double-click a process to view properties, use Find Handle or DLL to track file/registry use.
2) Process Hacker
Why it stands out:
- Open-source and highly extensible.
- Advanced features like service management, network connections, and memory viewing. Key features:
- Customizable columns, detailed graphs, plugin support.
- Can terminate stubborn processes and inspect threads. Notes:
- Some antivirus tools flag it due to powerful capabilities; download from the official repo and use responsibly.
3) Windows Task Manager (built-in)
Why it stands out:
- Installed by default and easy for everyday tasks.
Key features: - Simple process list, startup impact, performance graphs.
- Good for quick checks and terminating misbehaving apps. Limitations:
- Less detailed than Sysinternals tools.
Comparison (Windows)
Tool | Strengths | Best for |
---|---|---|
Process Explorer | Deep diagnostics, handle/DLL search, trusted | Power users, sysadmins |
Process Hacker | Extensible, open-source, powerful | Developers, advanced users needing extra features |
Windows Task Manager | Built-in, simple UI | General users, quick tasks |
Best free process viewers for macOS
1) Activity Monitor (built-in)
Why it stands out:
- Included with macOS and sufficient for most users.
Key features: - CPU, Memory, Energy, Disk, and Network tabs.
- Inspect processes, sample, force quit, and view open files. How to use:
- Use the Energy tab to find battery-draining apps; sample a process for a snapshot of its stack.
2) htop (terminal)
Why it stands out:
- Lightweight, customizable terminal viewer with process tree and sorting.
Key features: - Colorized, real-time display; easy filtering and tree view with UIDs and PIDs. How to install:
- Via Homebrew: brew install htop. Run in Terminal; use F keys or shortcuts to sort and kill processes.
3) Glances
Why it stands out:
- Cross-platform, provides a consolidated system overview.
Key features: - CPU, memory, disk, network, process list and alerts. Runs in terminal or web UI. How to install:
- pip3 install glances or via Homebrew. Good for remote monitoring.
Comparison (macOS)
Tool | Strengths | Best for |
---|---|---|
Activity Monitor | Built-in, graphical | Most macOS users |
htop | Fast, keyboard-driven | Terminal users, admins |
Glances | Consolidated overview, remote-friendly | Developers, remote monitoring |
Cross-platform and remote-friendly tools
- Glances — cross-platform, lightweight, remote web UI.
- htop — available on Windows via WSL, Linux, macOS.
- Netdata — more focused on full-system monitoring with dashboards (heavier than process viewers).
- Prometheus + Grafana — for large-scale, long-term monitoring (requires setup).
How to interpret common metrics
- CPU %: high short spikes are normal; sustained 80–100% indicates CPU-bound process.
- Memory (RSS): shows resident memory; watch for steady growth (memory leak).
- Disk I/O / Wait: high I/O suggests heavy file access or swapping.
- Threads / Handles: excessive counts may indicate resource leaks.
- Start time & uptime: frequent restarts can point to crashes or supervisor processes.
Safety tips when inspecting and killing processes
- If unsure, Google the process name before terminating.
- Avoid killing system processes (lsass, wininit, kernel_task). On macOS, kernel_task and launchd are critical.
- Use “suspend” or “sample” first to inspect behavior without terminating.
- Run advanced tools as admin/root only when necessary.
- Keep backups and create restore points before making system-level changes.
Example workflows
-
Find a CPU hog (Windows)
- Open Process Explorer, sort by CPU, expand process tree to find parent process, check command line and loaded modules, suspend or kill if confirmed malicious.
-
Diagnose memory leak (macOS)
- Use Activity Monitor to sort by memory; sample the top process to inspect thread activity; use Terminal htop for continuous observation.
-
Remote quick-check
- Install Glances on the remote host, run glances -w to use the web UI, inspect process list and set alerts.
Conclusion
For basic needs, built-in tools (Windows Task Manager, macOS Activity Monitor) are sufficient. For power users and investigators, Process Explorer (Windows) and terminal tools like htop or Glances (macOS) provide deeper insight. Choose tools that balance detail with safety, and always verify unknown processes before terminating them.