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Focus Mode / Site Blocker

Block distracting websites during focus sessions with a configurable blocklist and session timer.

Tested tool guide Tested browser tools Checked August 16, 2026

What Focus Mode / Site Blocker does and how it behaves

Focus Mode / Site Blocker pairs a configurable website blocklist with a countdown for a defined work or study interval. Add the sites that commonly interrupt the task, choose a session length, and start the session to make that list active until the timer finishes. The important distinction is scope: configuring the list is not the same as starting a session, and a browser-based blocker is not a network-wide restriction covering every browser, application, device, or internet connection.

How the result is produced

1

Configure the blocklist

Add each distracting destination to the session's blocklist using the website controls provided by the tool. Use recognizable site addresses rather than descriptive labels such as "social media." Review the completed list before starting, especially when a service uses several domains or subdomains. The blocklist identifies the destinations the focus session should restrict; it does not itself define how long the restriction lasts.

2

Run the timed session

Set the desired focus duration and start the session. The timer establishes the period during which the configured list is treated as blocked. When the countdown reaches its end, the timed restriction ends as well. This makes the tool appropriate for bounded intervals such as a writing sprint or study block, rather than an indefinite administrative ban on particular websites.

Good uses

  • Block social media and discussion sites during a 25-minute writing sprint.
  • Exclude video, gaming, and messaging destinations while completing a timed study interval.
  • Temporarily restrict news and shopping sites during a scheduled bookkeeping or email-processing session.

Limits and checks

  • Check every entered address before starting. A misspelled hostname will identify the wrong destination or fail to match the intended site.
  • Do not assume that one entry automatically covers every subdomain, alternate domain, mobile address, or shortened link used by the same service.
  • Treat the session as a browser-level focus aid, not as parental control, network filtering, or protection against access from another browser, device, or application.

Common questions

Does adding websites to the blocklist start blocking them immediately?

No. The list specifies which destinations belong to a focus session, while the timer specifies the session's duration. Start the session after reviewing both settings. If you only prepare the list and leave the timer inactive, you have configured a future session rather than begun a timed restriction.

Can this block the same sites on my phone or another browser?

No. The tool runs in the browser and does not configure another device, a router, DNS service, or operating-system policy. Its blocklist and session state are not uploaded for enforcement elsewhere. A phone, separate browser profile, private window, or unrelated application therefore should not be assumed to share the active restriction.

References and verification

The behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.

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