How to Block Distracting Websites on Chrome and Firefox

If you have ever opened a new tab to check one thing and resurfaced forty minutes later on your fifth YouTube video, you already know the problem. Distracting websites are not an accident — social feeds, news sites, and video platforms are deliberately engineered to hold your attention. Willpower alone is a weak defence against a system designed by thousands of engineers to beat it.

The good news is that you do not need more willpower. You need structure. Blocking distracting websites removes the decision from the moment of temptation and settles it in advance, when you are calm and thinking clearly. This guide covers every practical way to do it on Chrome and Firefox — the free built-in methods, their real limitations, and the faster approach most people end up using.

The manual ways to block a website (and where they fall short)

Before installing anything, it is worth knowing what your computer can already do. These methods are free, but each has a catch.

• Editing the hosts file. On both Windows and macOS you can redirect a domain to nowhere by adding a line to your system hosts file. It works system-wide across every browser, but it is fiddly, requires admin access, offers no scheduling, and is trivial to undo the moment you feel the urge.
• Screen Time (macOS/iOS) and Focus (Windows). Apple’s Screen Time and Microsoft’s Focus tools can limit categories of sites and apps. They are decent for broad limits but clumsy for a specific work-hours blocklist, and the browser-level controls are shallow.
• Router-level blocking. Some routers let you block domains for the whole network. Great for a household rule, useless once you switch to mobile data or a different network.

The common thread: these methods are all-or-nothing, hard to schedule, and easy to bypass in a weak moment. For focused work, you want something that lives where the distraction happens — in the browser — and that you can configure in seconds.

The faster way: a browser extension

A dedicated website blocker extension runs inside Chrome or Firefox and intercepts distracting pages before they load, redirecting you somewhere neutral instead. Setup takes under a minute, blocking can follow a schedule, and good blockers sync your rules across devices so you are not reconfiguring everything on your laptop and desktop separately.

If you want the full landscape, we compared the six most popular options in the best website blockers for 2026. The rest of this guide uses SiteBlocker because it keeps every blocking feature free and collects no browsing data, but the steps map closely to most extensions.

How to block a distracting website, step by step

1. Install the extension. Add SiteBlocker to Chrome or Firefox from the store. You can start immediately — no account is required, though signing in enables cross-device sync.
2. Add the sites you lose time to. Open the extension and create a blocklist. Add the domains that pull you in — twitter.com, youtube.com, reddit.com, whatever yours are. You can add as many as you like; there is no site cap on the free tier.
3. Choose what happens when you visit them. By default, a blocked site redirects to a calm block page instead of loading. That small pause is often all it takes to break the reflex.
4. Test it. Try visiting one of the sites. If you land on the block page, you are done.

A handy shortcut: on any page you want to block, right-click and add it to a blocklist straight from the context menu, without opening the extension at all.

Block on a schedule, not all day

Blocking a site around the clock is a blunt instrument — you probably do want to see Instagram at 8pm, just not at 10am. Scheduled blocking solves this. You set the hours and days a blocklist is active, and it enforces itself only then.

A common setup is to block social media and news from 9am to 5pm on weekdays and leave evenings and weekends open. Because the schedule is automatic, you never have to remember to turn blocking on — it simply happens. Scheduling is one of the features BlockSite and Freedom put behind a paywall, which is worth knowing if you are comparing SiteBlocker to BlockSite.

Whitelist mode: allow only what you need

Some work demands the opposite approach: instead of blocking a handful of bad sites, block everything except an approved list. Whitelist mode (sometimes called allow-only mode) does exactly that. If you are writing a report and only need your docs, your email, and one reference site, whitelist those three and the rest of the web disappears until you turn it off. It is the strictest, most focused setting available and ideal for deep-work sprints.

Focus Mode: block on demand

Schedules are great for recurring habits, but sometimes you just need to lock in right now. Focus Mode starts an on-demand session that blocks your distracting sites for a set length of time, regardless of the schedule. It includes a Pomodoro timer so you can work in focused intervals with short breaks — more on that in our Pomodoro Technique guide. You can run it soft (a gentle nudge you can override) or hard (no escape until the timer ends) depending on how much you trust yourself that day.

If you are a student

Studying is where distraction hurts most, because the work is cognitively demanding and the escape hatch is one tab away. Set up a “study” blocklist with your usual time-wasters, run it in hard Focus Mode during study blocks, and use whitelist mode during exam prep to allow only your course materials. Because rules sync across devices, the same blocks apply on your laptop in the library and your desktop at home.

If you work from home

Remote work removes the ambient accountability of an office, and the same machine you work on is the one you relax on. A weekday 9-to-5 schedule on social and news, plus a whitelist for meeting-heavy afternoons, rebuilds some of that structure. Pair it with Focus Mode for the two or three deep-work blocks that actually move your projects forward.

Block by keyword, not just by domain

Sometimes the distraction is not a whole website but a topic. Keyword blocking (a Pro feature) blocks any page whose URL, title, or content contains words you choose — so you can block, say, anything mentioning a particular game or news story across the entire web, without listing every site by hand. It is the one feature that goes beyond simple domain blocking, and you can see everything Pro includes on the pricing page.

Start small. Block the two or three sites that cost you the most time, run a schedule for one week, and add more only if you need to. An over-aggressive blocklist you disable after a day helps no one.

Ready to reclaim those forty-minute detours? Add SiteBlocker to Chrome or Firefox here and set up your first blocklist in under a minute.