Can I block websites on a Mac without an app?

Yes. macOS Screen Time can restrict specific sites system-wide, and you can also add entries to the /etc/hosts file. Both work, but both are easy to undo in a moment of temptation.

How do I block a website in Safari on a Mac?

Open System Settings > Screen Time > Content & Privacy > Content Restrictions, set Access to Web Content to 'Limit Adult Websites', then add your site under 'Never Allow'. Safari will refuse to load it.

Does Screen Time block websites in Chrome and Arc too?

Screen Time's 'Never Allow' list applies system-wide, so it affects Chrome, Arc, Brave, and Edge as well — but the block is only as strong as your willingness to leave it switched on.

What's the most reliable way to block distracting sites while working?

A session-based blocker. Instead of a permanent list you can toggle off, blocking is tied to a focus session with a timer, so the distraction is unavailable for the whole block of work.

Guide

How to block websites on a Mac

There are four practical ways to keep distracting sites off your Mac — Screen Time, the hosts file, a browser extension, or a focus-session blocker. Here's how each one works, and where each one falls down.

Use Screen Time (built into macOS)

Open System Settings, choose Screen Time, then Content & Privacy. Turn on Content & Privacy, open Content Restrictions and set Access to Web Content to 'Limit Adult Websites'. Add each site you want blocked under 'Never Allow'. This applies across Safari, Chrome, Arc, Brave and Edge.

Best for: a permanent block on a handful of sites. Weakness: it takes about ten seconds to switch off, and in the moment you want to be distracted, ten seconds is nothing.

Edit the hosts file

Open Terminal and run sudo nano /etc/hosts. Add a line such as 127.0.0.1 www.example.com for each site, save with Control-O, exit with Control-X, then run sudo dscacheutil -flushcache. Requests to those domains stop resolving.

Best for: technical users who want a system-level block. Weakness: fiddly, needs an admin password, breaks nothing gracefully, and you must remember the www and non-www versions of every domain.

Install a browser extension

Add a site-blocking extension from the Chrome Web Store or Safari Extensions and list the domains you want blocked. Extensions can also allow blocking on a schedule.

Best for: people who only ever use one browser. Weakness: the block covers that browser only — open a different browser, or a desktop app like Slack or YouTube's native client, and you're straight back where you started.

Use a focus session blocker

Install a focus app that ties blocking to a timed session. Choose the apps and sites that pull you off track, start a session, and everything on the list is unavailable until the timer ends.

Best for: getting actual work done. Because the block starts and stops with the work, there is no permanent list to maintain and no decision to make when the urge hits.

Which one should you use?

If you need one site gone forever, Screen Time is enough. If the problem is that you drift off during work — a tab here, a desktop app there — a permanent block list is the wrong shape for it. You end up maintaining a list, or turning it off "just for a second".

Intentional takes the session approach: pick your apps and sites, start a timer, and both are out of reach until you're done. It covers native Mac apps as well as Safari, Chrome, Arc, Brave and Edge, so there's no side door. More on choosing a focus app for Mac.

Common questions

Can I block websites on a Mac without an app?: Yes. macOS Screen Time can restrict specific sites system-wide, and you can also add entries to the /etc/hosts file. Both work, but both are easy to undo in a moment of temptation.
How do I block a website in Safari on a Mac?: Open System Settings > Screen Time > Content & Privacy > Content Restrictions, set Access to Web Content to 'Limit Adult Websites', then add your site under 'Never Allow'. Safari will refuse to load it.
Does Screen Time block websites in Chrome and Arc too?: Screen Time's 'Never Allow' list applies system-wide, so it affects Chrome, Arc, Brave, and Edge as well — but the block is only as strong as your willingness to leave it switched on.
What's the most reliable way to block distracting sites while working?: A session-based blocker. Instead of a permanent list you can toggle off, blocking is tied to a focus session with a timer, so the distraction is unavailable for the whole block of work.