Zenblock

Features

• Block list — in one place, either block a site completely or give it a daily time limit. Supports bare domains (youtube.com, also matches subdomains), wildcards (*.reddit.com), and path prefixes (reddit.com/r/all).
• Daily time limits — give a site a daily budget (e.g. 30 min) right from the block list. Zenblock tracks active usage with a live status bar, and once the budget is spent the site is blocked for the rest of the day (resets at midnight).
• Categories — flip a single switch to block a curated group of sites: Social Media, Video & Streaming, News, Gaming, Shopping, or Adult. Add or remove sites per category.
• Schedule — choose "Always on" or "Only on schedule", and define day + time windows (overnight windows supported).
• Zen mode — a time-boxed lockdown with its own block list and categories, edited separately from your everyday lists (Settings → Zen). Optionally also include your main block list/categories with a toggle. Begin a session with a duration; while it runs, the in-scope sites are blocked even if the master switch is off, and every settings control is locked. Changing anything or stopping early requires retyping a ~100-word passage, which grants a 2-minute editing window before it re-locks. (It's a strong willpower lock, not tamper-proof — see the note below.)
• Block in private windows — toggle straight from the toolbar popup to enable the blocking in close private/incognito windows too.
• Custom block page — a calm, on-brand page with your own message, or optionally redirect blocked visits to a URL of your choice.
• Quick controls — toolbar popup with a master switch, mode toggle, one-click "Block this site", live time-limit status, the private-windows switch, zen mode (top-right), and a daily blocked-attempts counter.
• Light / dark / system theme, and everything is stored locally (no account, no tracking).