How do I block websites across all browsers on Mac?

Use a method that works below the browser. Editing the /etc/hosts file in Terminal redirects a domain for Safari, Chrome, Firefox, and Arc at once. A system-level app like the free Focuh desktop app does the same during a focus session and adds a timer you can't casually undo. Browser extensions and Screen Time only cover one browser each, so a site you block in Safari still opens in Chrome unless the block lives at the OS level.

Why does a website I blocked still open in another browser?

Because the block was scoped to one browser. Screen Time governs Safari only, and an extension governs the browser it's installed in. The autopilot move when you hit a blocked site is to open it somewhere else, and a single-browser block leaves every other browser open. To close that gap, block below the browser with the hosts file or a system-level app, and the same site is unreachable everywhere at once.

How do I block a website in every browser on Mac for free?

Two free routes cover every browser. The /etc/hosts file is built into macOS and redirects a domain across all browsers with no extra software, though it has no timer and is easy to edit out. The free Focuh app blocks at the system level during a focus session, covering Safari, Chrome, Firefox, and Arc together, and pairs the block with a timer and a menu-bar countdown. Both are free; the app adds friction the hosts file doesn't.

Does the hosts file block websites in all browsers?

Yes. The hosts file works at the operating-system level, mapping a domain to 127.0.0.1 before any browser resolves it, so Safari, Chrome, Firefox, and Arc are all blocked at once. The catches: it has no timer, you have to know each subdomain to be thorough, and removing the block takes about thirty seconds in Terminal, so nothing stops you from undoing it on impulse.

Is a system-level blocker harder to bypass than a browser extension?

Generally yes. A browser extension can be toggled off in a couple of clicks from the browser's settings. The free Focuh Mac app blocks using macOS Accessibility APIs and ties the block to a running focus session, so there's no per-browser switch to flip and the block resists a quick mid-session disable. No software is unbreakable, but OS-level blocking puts more friction between you and the bypass than an extension does.

Will blocking websites across all browsers also block apps?

The hosts file blocks any app that resolves the domain through normal DNS, so many native apps are covered too, though some apps use hardcoded servers that slip past it. A system-level focus app like Focuh is built to block distracting apps and sites together during a session. If your distraction is a native app like a desktop client rather than a browser tab, lean on the app-aware blocker rather than the hosts file alone.

How do I block websites across browsers during work hours only?

Use a session-based tool rather than a permanent toggle. The free Focuh app turns blocking on when you start a focus session and off when it ends, so there's nothing to remember to re-enable, and it covers every browser at once. The hosts file has no timer, so for work-hours blocking you'd be editing it twice a day by hand. A session-based, all-browser block is the cleaner fit for a recurring work schedule.

Do I still need a browser extension if I have a system-level blocker?

Not for blocking — a system-level app already covers every browser, so an extension would be redundant. You might keep a Chrome extension if you want lightweight, browser-only blocking on a machine where you don't want a desktop app, or if you're on Windows or Linux where the Mac app doesn't run. On a Mac, the system-level app is the more complete option and makes per-browser extensions unnecessary.

macOSblock websites all browserssystem-level blockingwebsite blockerfocus

How to Block Websites Across All Browsers on Mac (Free, 2026)

June 7, 202610 min readFocuh

The reason a website you "blocked" keeps reappearing on your Mac usually isn't willpower — it's scope. You blocked it in Safari, then opened it in Chrome. This guide shows you how to block websites across all browsers on Mac for free, using methods that work below the browser so the block applies to Safari, Chrome, Firefox, and Arc at the same time.

There are two free routes that genuinely cover every browser: the hosts file and a system-level focus app. Single-browser tools — Screen Time and extensions — are covered too, so you can see exactly why they leave a door open.

Why single-browser blocks fail

Screen Time blocks Safari. A Chrome extension blocks Chrome. Each one does its job, and each one leaves every other browser untouched. When you hit a blocked site, the autopilot reaction isn't to give up — it's to open the same site somewhere else. If you have three browsers installed, a Safari-only block is really a "block in one of three places" block.

Blocking across all browsers means moving the block below the browser layer, to the operating system. Once the block lives at the OS level, there's no second browser to escape to, because the request never resolves no matter what opens it.

Method 1: Edit the hosts file (covers every browser, free)

The hosts file maps a domain to your own machine before any browser can reach the real server. It's built into macOS, free, and universal.

Open Terminal and run:

sudo nano /etc/hosts

Enter your password, then add a line for each domain and its common subdomains:

127.0.0.1 reddit.com
127.0.0.1 www.reddit.com
127.0.0.1 m.reddit.com

Save with Control+O, exit with Control+X, then flush DNS:

sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

The site is now blocked in Safari, Chrome, Firefox, and Arc at once. The trade-off: there's no timer, you have to list every subdomain yourself, and removing the block takes about thirty seconds — so nothing stops you undoing it on impulse. The mechanics are covered in more depth in system-level website blocking on macOS.

Method 2: A system-level focus app (every browser, plus a timer)

The hosts file blocks everywhere but has no friction and no timer. A system-level focus app fixes both while keeping the all-browser coverage.

The free Focuh desktop app for Mac blocks sites at the operating-system level during a focus session. While the session runs, the blocked sites are unreachable in Safari, Chrome, Firefox, and Arc simultaneously, and Focuh pairs the block with a focus timer, a menu-bar countdown, and a task list — so the block turns on when you start working and off when you finish. Because it uses macOS Accessibility APIs rather than a per-browser setting, it's harder to switch off mid-session than an extension or Screen Time.

This is the method for the site you've "blocked" five times and keep ending up on anyway. Removing every browser route at once, and binding the block to a session instead of a manual toggle, is what makes it hold. The fuller argument is in system-level vs browser website blocking.

Ways to block websites across all browsers on Mac, compared

Method	Free?	Covers all browsers?	Has a timer?	Bypass friction
Screen Time	Yes	No (Safari only)	No	Low
Browser extension	Yes	No (one browser)	Sometimes	Low
Hosts file	Yes	Yes	No	Low (easy to edit out)
SelfControl	Yes	Yes	Yes — set duration	High during a block
Focuh Mac app	Yes	Yes (OS-level)	Yes — focus session	High

The two bottom rows are the only ones that both cover every browser and resist a quick undo. The difference: SelfControl is a pure timed blocker you set for a fixed duration, while Focuh ties blocking to a focus session and wraps a timer, tasks, and a menu-bar countdown around it. If you're weighing the dedicated tools, the best website blockers for Mac in 2026 guide lines them up in detail.

Where Screen Time and extensions still fit

All-browser blocking is the goal, but single-browser tools aren't useless — they're just narrower.

Screen Time is fine when your distraction lives entirely in Safari and you trust your own passcode. It's built in and takes two minutes. The limit is that it ends at Safari's edge.
A browser extension is the lightest option if you only ever use one browser. The catch is in the name — it blocks that browser and no other. For a single-browser habit, that's enough; for anything else, it's the scope problem all over again.

If you find yourself switching browsers specifically to dodge a block, that's the signal to move up to an OS-level method. The switch is the symptom; all-browser blocking is the cure.

Why the all-browser approach changes the daily friction

There's a second benefit beyond coverage. With a per-browser block, you're re-deciding all day whether a site is reachable — block here, open there, negotiate with yourself each time. An all-browser, session-based block collapses that into one decision: "the next 50 minutes are for work." The block follows from it, the same in every browser, and you stop relitigating the question every twenty minutes.

That's the real reason single-browser blocks keep failing. It isn't only that they leave another browser open — it's that they keep the choice live all day, and a live choice is one you'll eventually lose. Removing the choice in every browser at once is what makes the block stick.

Which method should you choose?

"I use more than one browser" — Start with the hosts file for a free universal block, or the system-level app if you also want a timer.

"I keep switching browsers to escape the block" — Use system-level blocking. The free Focuh app covers every browser during a session and resists a mid-focus undo.

"I only ever use Safari and trust myself" — Screen Time is enough, with the caveat that it ends at Safari.

Every option here is free, so start with the lightest one that actually holds. If you've blocked the same site in one browser over and over and it keeps coming back, the fix isn't more willpower — it's blocking below the browser. Download the free Focuh app to block sites across every browser on your Mac today, or compare alternatives with the SelfControl alternative breakdown.