A free, open-source, featherweight system monitor for Mac. Live RAM and CPU usage in your menu bar, colored from green to red, and every process one click away — with a button to quit the one that's eating your Mac.
brew install --cask simonsruggi/tap/ramdock
- Why RamDock
- Features
- Screenshots
- Install
- Use it with Claude and other AI assistants (MCP)
- How the numbers are measured
- How light is it
- Privacy
- Build from source
- FAQ
- More open source Mac apps
- License
When the fans spin up or the Mac starts to stutter, the question is always the same: what is eating my RAM or my CPU right now, and can I kill it? Activity Monitor answers it, but it's a full window, a dozen columns and three clicks away.
RamDock keeps the answer in the menu bar:
- Two numbers, always visible. System RAM and CPU usage, green when things are calm, red when they aren't.
- One click to the culprit. Every process with its CPU and memory, sorted by whichever is hurting.
- One more click to fix it. Quit the process from the list; force quit it if it doesn't listen.
- It doesn't become the problem. A monitor that eats resources defeats its purpose: RamDock is written in plain AppKit and idles at a few megabytes and near-zero CPU.
- Live menu bar readout —
RAM 74% CPU 23%, refreshed every 3 seconds, each value colored on a green → yellow → red scale. - Process list — CPU % and memory for every process you own, sorted by RAM or CPU, with app icons.
- Search by process name or PID.
- Quit and Force Quit — the ✕ on each row sends a normal quit (SIGTERM); ⌥-click or right-click → Force Quit sends SIGKILL. Right-click → Copy PID.
- Customizable menu bar — show RAM and CPU, RAM only or CPU only; text size from 9 to 18 pt; label and value colors from presets or any color you pick; a live preview shows the result as you change it.
- This Mac — model, chip, CPU cores (performance and efficiency), GPU cores, memory, free storage, macOS version and uptime.
- Open at login and automatic updates (Sparkle).
- Native, universal (Apple silicon and Intel), light and dark mode.
Homebrew
brew install --cask simonsruggi/tap/ramdockDirect download — grab RamDock.zip from the latest release, unzip it and drag RamDock.app to Applications. The app is signed with a Developer ID and notarized by Apple.
RamDock lives in the menu bar only — there's no Dock icon. Turn on Settings → Open at login to have it start with your Mac. Updates are checked automatically; Settings → Check for Updates… checks right away.
Requires macOS 14 Sonoma or later.
RamDock 1.1.0 and later is also an MCP server: AI assistants that support the Model Context Protocol can read its data and answer questions about it.
| Tool | What it returns |
|---|---|
get_system_usage |
Memory used, total and swap, CPU load, model, chip, macOS, uptime, free disk |
list_top_processes |
The processes using the most RAM or CPU right now, optionally only apps |
Try asking:
- "Why is my Mac slow right now?"
- "Which apps are using the most memory?"
- "Is my Mac swapping? How much RAM is free?"
Claude Code
claude mcp add ramdock -- /Applications/RamDock.app/Contents/MacOS/RamDock --mcpClaude Desktop, Cursor and other MCP clients — add this to the client's MCP config (Claude Desktop: Settings → Developer → Edit Config; Cursor: ~/.cursor/mcp.json):
{
"mcpServers": {
"ramdock": {
"command": "/Applications/RamDock.app/Contents/MacOS/RamDock",
"args": ["--mcp"]
}
}
}The menu bar app doesn't need to be running: the client starts RamDock in the background with --mcp, without any window or menu bar icon.
Everything is measured on the spot on your Mac. The tools only read: an AI can't quit or kill processes through RamDock.
| Source | Matches | |
|---|---|---|
| Menu bar RAM | host_statistics64: app memory + wired + compressed, over physical memory |
Activity Monitor → Memory → Memory Used |
| Menu bar CPU | host_statistics CPU ticks, averaged over all cores |
Activity Monitor → CPU → User + System |
| Process CPU | proc_pid_rusage user + system time between two samples |
Activity Monitor's % CPU (100% = one core) |
| Process memory | proc_pid_rusage physical footprint |
Activity Monitor's Memory column |
A resource monitor shouldn't be a resource problem. Measured with footprint on an M5 MacBook Pro:
- ~13 MB of memory at launch, ~27–35 MB after using the panel.
- ~0.15 s of CPU per minute with the panel closed — the status item reads two kernel counters every 3 seconds and redraws only when a number changes.
- The process list is sampled only while the panel is open; closing it stops sampling and releases the list.
The architecture notes in PROJECT.md explain the choices, including why RamDock uses a custom panel instead of NSPopover (an empty popover alone keeps ~25 MB alive).
RamDock has no account, no analytics and no server. Process and system data is read locally and never leaves your Mac. The only network request is Sparkle's update check against this repository's appcast.xml.
git clone https://github.com/simonsruggi/RamDock.git
cd RamDock
./build-app.sh --install # builds a universal RamDock.app and copies it to /ApplicationsSwift Package Manager, one dependency (Sparkle). Without a Developer ID the app is signed ad-hoc.
Why don't I see kernel_task, WindowServer or other system processes?
macOS only lets an unprivileged app read the processes of the current user, and those are also the only ones you can quit without administrator rights. The menu bar totals do include the whole system.
The CPU of a process is above 100%. Is that a bug? No — as in Activity Monitor, 100% is one full core, so a process using four cores shows 400%. The menu bar CPU is the average across all cores, so it never exceeds 100%.
What's the difference between the ✕ and Force Quit? The ✕ asks the process to quit (SIGTERM), so apps can save and clean up. Force Quit (⌥-click or right-click) kills it immediately (SIGKILL) — use it when the process ignores the normal quit.
Why is the RAM percentage so high when I'm not doing much? macOS uses free memory for caches on purpose. RamDock reports Memory Used the same way Activity Monitor does, which excludes file cache; a high number with green color is fine, red means you're running short.
Is RamDock a free alternative to iStat Menus or Stats? For RAM and CPU, yes: RamDock focuses on those two numbers and on quitting the process behind them, and stays much smaller. If you need network, disk, sensors or battery graphs, those apps cover more.
Looking for other free, open source apps for your Mac? I keep Awesome Mac Open Source: 1,000+ maintained macOS apps sorted by GitHub stars, with the Homebrew command to install each one, refreshed every week.
MIT — see LICENSE. Issues and pull requests are welcome.
Made with ❤️ by Simone Ruggiero