PortKiller — macOS Menu Bar Port Killer

Instantly find and kill the process listening on any TCP port — right from your macOS menu bar. Free up :3000, :8080, :5432 and fix "address already in use" (EADDRINUSE) in one click.

PortKiller is a tiny, native macOS menu bar app for developers who constantly hit "port already in use". It auto-discovers every listening TCP port on your Mac, groups them by what they are (web server, database, dev tool, container, system), and lets you kill the process behind a port with a single click — no more hunting for PIDs with lsof and kill -9.

✨ Features

• 🔍 Auto-discovers all listening TCP ports — refreshed automatically (adaptive interval).
• ⚡ One-click kill — graceful SIGTERM, then SIGKILL if the process holds on; PID + port ownership re-validated before killing.
• 🗂️ Smart categories — ports grouped into Web Server · Database · Development · Container · System.
• ⭐ Favorites — pin the ports you care about (:3000, :5432…) to the top; persisted across launches.
• 👁️ Watched ports + native notifications — get a macOS notification when a watched port opens or closes.
• 🔎 Search & filter — by port number, PID, process name, command or user.
• 🌳 List or tree view — flat by category, or grouped by process (⌘T).
• 💣 Kill All — clear every visible port at once (with confirmation).
• 🪶 Native & lightweight — pure SwiftUI, LSUIElement (no Dock icon), no Electron, ~760 KB.

📦 Install

Download (recommended)

1. Grab the latest PortKiller.dmg from the Releases page.
2. Open the DMG and drag PortKiller.app into Applications.
3. Launch it — the network icon appears in your menu bar.

Gatekeeper note: the build is ad-hoc signed (not notarized). On first launch macOS may say "PortKiller can't be opened". Right-click the app → Open, then confirm — you only need to do this once. (Or: System Settings → Privacy & Security → Open Anyway.)

Build from source

See Build from source below.

🚀 Usage

Click the menu bar icon to open the popover:

• Click the ✕ next to a port to kill it (with a confirm step).
• Hover a row to reveal ★ (favorite) and 👁 (watch) toggles.
• Right-click a row for a context menu (kill, favorite, watch, and process details).

Shortcut	Action
⌘R	Refresh
⌘T	Toggle list/tree
⌘K	Kill all
⌘Q	Quit

🛠 Build from source

Requirements: macOS 15+ and Swift 6 / Xcode 16.

git clone https://github.com/dev-toolings/httportkiller-menubar.git
cd httportkiller-menubar

swift test            # run the test suite
swift build -c release

# Package a signed .app and a drag-to-Applications DMG
Scripts/package_app.sh
Scripts/make_dmg.sh         # -> dist/PortKiller.dmg

open ".build/release/PortKiller.app"

🔬 How it works

PortKiller shells out to lsof -iTCP -sTCP:LISTEN -P -n +c 0 to enumerate every TCP listener, enriches each row with the process command line, and renders them in a native MenuBarExtra popover. Killing a port re-validates that the PID still owns the port, sends SIGTERM, waits, and escalates to SIGKILL only if needed — so you never nuke the wrong process.

❓ FAQ

"Error: listen EADDRINUSE: address already in use :::3000" — a stale dev server is still holding the port. Open PortKiller, find :3000, click ✕. Done.

Does it need admin rights? No. It can only kill processes owned by your user.

Does it phone home? No network access, no telemetry. Everything is local.

🙏 Attribution

This project adapts design and implementation ideas from productdevbook/port-killer (MIT). See THIRD_PARTY_NOTICES.md.

📄 License

MIT © 2026 MakFly