How do I block websites on Mac using Terminal?

Edit the hosts file with a command-line editor. Open Terminal, run sudo nano /etc/hosts, enter your password, and add a line like 127.0.0.1 www.example.com under the existing entries. Save with Control-O and Enter, exit with Control-X, then run sudo dscacheutil -flushcache to clear the DNS cache. The site now fails to load in every browser on the Mac. Repeat the line for each domain you want blocked, including the www and non-www versions.

Where is the hosts file on a Mac?

The hosts file lives at /etc/hosts on macOS. It's a plain text file that maps hostnames to IP addresses before your Mac asks a DNS server, so anything you point at 127.0.0.1 or 0.0.0.0 fails to resolve. You need administrator rights to edit it, which is why the command starts with sudo. Always edit it with a tool like nano rather than a word processor, so it stays plain text without hidden formatting.

Does editing the hosts file block websites in all browsers?

Yes — that's its main advantage over a browser extension. The hosts file works at the system level, so a domain you block there fails to load in Safari, Chrome, Firefox, Arc, and any other browser at once. You don't install anything per browser. The catch is that it only blocks by exact hostname, so you must add each subdomain you care about, and it does nothing to apps that connect directly by IP address.

Why is a blocked site still loading after I edited the hosts file?

Usually one of three things. The DNS cache hasn't cleared — run sudo dscacheutil -flushcache and sudo killall -HUP mDNSResponder. Or your browser cached the page — try a hard refresh or a private window. Or you blocked example.com but the site loads on www.example.com, or vice versa. Add both the www and non-www versions of every domain, flush the cache, and the block should take effect immediately.

Can you bypass a hosts file block?

Easily, which is the method's biggest weakness. Anyone with admin access can reopen /etc/hosts and delete the line in ten seconds, and there's no timer or password gate stopping them. A determined user can also switch to a DNS-over-HTTPS resolver in the browser, which routes around the hosts file entirely. The manual method is fine for honest mistakes and autopilot habits, but it's a speed bump, not a wall — for real friction you need a dedicated blocker.

Is editing the hosts file safe?

Yes, as long as you only add new lines and don't change the existing ones. The default entries — 127.0.0.1 localhost and ::1 localhost — must stay exactly as they are, since macOS relies on them. Add your blocked sites below those. If something breaks, you can always remove the lines you added and flush the cache to restore the original behavior. Keeping a backup with sudo cp /etc/hosts /etc/hosts.backup before you start is a sensible precaution.

Hosts file or a blocking app — which should I use?

Use the hosts file if you want a free, no-install method, you're comfortable in Terminal, and you mainly need to stop autopilot visits. Use a dedicated app if you want scheduling, a timer you can't cancel, an attempt counter, or coverage you can start and stop without editing a system file. The Focuh Mac app handles blocking during focus sessions without Terminal, and SelfControl offers a timed block you can't lift early. Many people use the hosts file as a baseline and an app for sessions.

Does the hosts file method work for blocking apps on Mac?

Only indirectly. The hosts file blocks domains, so it can break an app that loads its content from a blocked website over standard DNS. But many native apps connect directly to IP addresses or use their own resolvers, and those ignore the hosts file completely. If your goal is blocking apps rather than websites, the hosts file is the wrong tool — use a system-level blocker like the Focuh Mac app, which can block applications during a focus session.

block websites macTerminalhosts filemacOSwebsite blocker

How to Block Websites on Mac Using Terminal (Hosts File) — 2026

June 11, 20269 min readFocuh

The hosts file is the oldest free way to block a website on a Mac, and it still works in 2026. No app, no extension, no account — just one line in a system file and the site stops loading in every browser. This guide shows you exactly how to block websites on Mac using Terminal, step by step, then explains the real limits of the method so you know when to reach for something stronger.

The fast answer

To block a website on Mac using Terminal, open Terminal and run sudo nano /etc/hosts, enter your password, and add a line like 127.0.0.1 www.example.com below the existing entries. Save with Control-O, exit with Control-X, then run sudo dscacheutil -flushcache to clear the DNS cache. The site now fails to load in Safari, Chrome, Firefox, and every other browser on the Mac. It's free and system-wide — but it's also easy to undo, so it's a speed bump rather than a locked door.

How to block a website on Mac using Terminal, step by step

Open Terminal (Applications → Utilities, or search with Spotlight).
Back up the file first: sudo cp /etc/hosts /etc/hosts.backup. Enter your password when asked.
Open the hosts file for editing: sudo nano /etc/hosts.

Move the cursor below the existing lines and add one line per site:

127.0.0.1 www.youtube.com
127.0.0.1 youtube.com
127.0.0.1 www.reddit.com
127.0.0.1 reddit.com

Save with Control-O then Enter, and exit with Control-X.
Clear the DNS cache so the change takes effect: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder.

That's it. Open the blocked site in any browser and it fails to connect. Add both the www and non-www version of every domain — the hosts file matches the exact hostname, so blocking reddit.com alone won't stop www.reddit.com.

Why the hosts file blocks every browser at once

The reason this method beats a browser extension on coverage is where it sits. The hosts file is checked before your Mac asks a DNS server for an address, so when you point a domain at 127.0.0.1 (your own machine), the request goes nowhere. That happens at the system level, beneath every browser, which is why Safari, Chrome, Firefox, and Arc all hit the same wall without you installing anything in each one.

A Chrome extension, by contrast, only controls Chrome. The moment you open Safari, its block is gone. So for pure cross-browser coverage at zero cost, the hosts file genuinely wins — the catch is everything else, which is the next section.

Where the Terminal method falls short

The hosts file is blunt. It's worth knowing its limits before you rely on it:

It's trivial to undo. Anyone with admin access can reopen /etc/hosts and delete the line in seconds. There's no timer, password, or session — nothing stops a moment of weakness.
No scheduling. You can't block a site only during work hours or only on weekdays. It's on until you manually remove the line.
Exact hostnames only. You must list every subdomain. Block youtube.com and www.youtube.com, or one of them slips through.
It doesn't reliably block apps. Many native apps connect by IP or use their own resolver, ignoring the hosts file entirely.
DNS-over-HTTPS can route around it. A browser set to use its own secure DNS resolver can bypass the hosts file completely.

None of that makes the method useless. For stopping autopilot visits — the reflexive youtube.com you type without deciding to — a hosts file block is often enough, because the friction of editing a system file is more than the reflex can be bothered with. It's the deliberate, determined bypass it can't stop.

Hosts file vs a blocking app, compared

Feature	Hosts file (Terminal)	Focuh Mac app	SelfControl
Free	Yes	Yes	Yes
Blocks all browsers	Yes	Yes	Yes
Blocks native apps	No	Partially	Network-level
Scheduling / sessions	No	Yes	Timed block
Hard to undo	No	Medium	High
Needs Terminal	Yes	No	No
Attempt counter	No	Yes	No

If the hosts file's "easy to undo" row is the dealbreaker for you, that's the signal to use an app. For a fuller comparison of Mac options, see the best free app blocker for Mac, and for the general approach, how to block websites on Mac covers every method side by side.

How to unblock a site you blocked in Terminal

Reversing it is the same process. Run sudo nano /etc/hosts, delete the lines you added, save with Control-O and Control-X, then flush the cache again with sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder. If you made the backup in step 2, you can also restore it wholesale with sudo cp /etc/hosts.backup /etc/hosts and flush. The site loads again immediately. This ease of reversal is exactly why the method is honest as a habit-breaker but weak as a lockdown.

When to use an app instead

Reach for a dedicated blocker when the manual method's weaknesses are the things you actually need solved. If you want a block you can't cancel in a weak moment, SelfControl sets a timer that can't be lifted until it runs out. If you want blocking tied to focus sessions, an attempt counter, and no system-file editing, the free Focuh Mac app handles it through a normal interface and can block apps as well as sites during a session. And if your distraction lives in Chrome and you also want a browser layer, the free Focuh Chrome extension covers that.

The hosts file and an app aren't mutually exclusive. A common setup is a hosts file as a permanent baseline for the handful of sites you never want, plus an app for time-boxed focus sessions where you want stronger, harder-to-cancel blocking. Why OS-level blocking beats the browser-only kind is covered in system-level vs browser website blocking.

Which approach should you pick?

You want a free, no-install block and you're fine in Terminal — use the hosts file method above for your permanent blocklist.
You want scheduling, sessions, or app blocking without editing system files — use the free Focuh Mac app.
You want a block you can't undo in a weak moment — use SelfControl's timed block.
Your distraction is mostly in Chrome — add the free Focuh Chrome extension on top.

The hosts file is the right first tool for honest, autopilot habits — free, system-wide, and already on your Mac. When you need scheduling or a block you can't cancel, that's where an app earns its place. Get the free Focuh Mac app when the manual method isn't enough on its own.