Free & Open Source
K9 Web Protection

Web Protection
for Your Family

Free, open-source parental control for Mac and Windows. Block adult content, filter harmful websites, and keep your family safe online. No subscription required.

Download for macOS
Coming Soon Windows
Extension for Chrome

macOS 12+ · Apple Silicon & Intel  |  Windows 10/11 64-bit  |  Chrome Extension

2
Layers of protection
28K+
Filter rules
Free
No subscription
Open
Source code

Everything you need to stay protected

Two independent layers of protection work together to block harmful content before it reaches your screen.

🛡️

Layer 1 — DNS Blocking

Blocks harmful domains at the system level via /etc/hosts. Works for every app and browser on your Mac, even offline.

🔍

Layer 2 — Proxy Filter

A local HTTPS proxy inspects URLs and keywords in real time. Works in every browser — Chrome, Firefox, Safari, Brave — including incognito and private browsing modes.

🔑

Block & Allow Lists

Add custom domains to your blocklist, or whitelist specific sites that the built-in filter would otherwise block — full control in your hands.

🗝️

Keyword Filtering

10,527 built-in keywords always active. Add your own words or phrases — any URL containing them is blocked immediately by the proxy.

🎛️

Content Toggles

Individually switch adult content, image & video search, YouTube, and Safe Search enforcement on Google, Bing, and DuckDuckGo.

🔒

Password Protection

Lock all settings and the uninstall process behind a password. Nothing can be changed or removed without entering it first.

🔄

Auto-Restart Watchdog

A background agent re-locks binaries and re-enables the proxy every 10 seconds. Cannot be defeated by force-quitting the app.

🔐

100% Local & Private

All filtering runs on your machine. No URLs, history, or stats ever leave your device. No telemetry, no accounts, no internet required.

See it in action

A native macOS dashboard — clean, fast, and always in control.

K9 Web Protection
K9 Web Protection dashboard showing Protection Active status, proxy running on port 8080, and 28,460 filter rules
24,233
Blocked domains
4,227
URL patterns
10,527
Keywords
28,460
Total rules

Up and running in minutes

No technical knowledge required.

1

Download & install

Download the zip, unzip it, and drag K9 Web Protection.app to your Applications folder. On first launch, macOS may show a Gatekeeper warning — go to System Settings → Privacy & Security → Allow Anyway.

2

Change the default password

Open K9 Web Protection, go to Settings, and change the password. The default password is shown below — update it immediately so only you can disable protection.

k9.khaleel.eu Copy
3

Enable protection

Click "Enable Protection" on the dashboard. Both layers activate instantly — all browsers are now filtered.

4

Stay protected

K9 runs silently in the background, survives restarts, and watches over itself. Set it and forget it.

Frequently Asked Questions

Everything you need to know about K9 Web Protection.

Is K9 Web Protection really free?
Completely free, forever — no premium tier, no subscription, no hidden fees. The full source code is open on GitHub for anyone to audit or build from.
Does it work in all browsers, including incognito?
Yes. K9 operates at the OS network level — not as a browser extension. The system proxy (Layer 2) and hosts file (Layer 1) filter traffic in every browser: Chrome, Firefox, Safari, Brave, Arc, and others. Incognito and private browsing modes are fully covered.
Does K9 collect any of my data?
No. All filtering runs 100% locally on your machine. No URLs, browsing history, or statistics ever leave your device. There is no telemetry, no account required, and no internet connection needed for the filter to work.
What content does K9 block?
K9 blocks adult domains (built-in database), adult URL patterns, explicit keywords, explicit image search, YouTube (optional), and enforces Safe Search on Google, Bing, and DuckDuckGo. You can also add custom domains to the blocklist or allowlist at any time.
What is the default password?
The default password is k9.khaleel.eu. Change it immediately in Settings after first launch — the default is public knowledge and anyone who knows it could disable protection.
Will K9 slow down my internet?
Negligibly. Layer 1 (hosts file) adds zero latency. Layer 2 (local proxy) routes traffic through 127.0.0.1:8080 — a localhost connection — adding under 1ms of overhead. In everyday browsing the difference is imperceptible.
Can K9 be bypassed with a VPN?
VPN apps that route through the system proxy are still filtered by Layer 2. For maximum protection, set a strong password — disabling K9 always requires authentication first.

Free. Forever.

No ads, no subscriptions, no data collection. Just protection.

Download free for macOS
Coming Soon Windows
Extension free for Chrome
K
Khaleel Ahmad
Data & AI Engineer

K9 Web Protection started as a personal project and grew into a free, open-source app I'm happy to share with the community. Built in Go for macOS and Windows, it works at the OS level with no subscriptions, no data collection and no compromises. If it has helped you or your family stay safe online, consider supporting the work.