LeechBlock NG vs Otto
We give LeechBlock NG a 3.4 GPA and Otto a 3.2, out of 4.0. LeechBlock NG grades higher on the free plan. They get the same grade on value for money, features, ease of use and platforms.
Price, platforms and features side by side. The table says where each price was read and when.
LeechBlock NG
Free browser extension that blocks time-wasting sites on a schedule
Free
Otto
Pomodoro timer and website blocker extension for Chrome
Free plan · from $29/yr
How we grade them
| 3.4GPALeechBlock NGVery good | 3.2GPAOttoVery good | |
|---|---|---|
| Value for money | AIt's entirely free and there's no paid version. One developer builds it as a hobby project and publishes the source code on GitHub. | APro is $29 for one year, paid once, or $66 for a lifetime licence. That's about half what a typical focus app costs for the year. Lifetime also covers the planned mobile app at no extra cost, and refunds are given within 14 days. |
| Free plan and trial | AThe complete extension is free: up to 30 block sets, time limits, lockdown, password pages and the rest. There's nothing to upgrade to. | BFocus sessions are unlimited for free. But you get 4 focus block rules, 2 scheduled blocking rules and 1 autoblock rule, and analytics only cover 7 days. There's no free trial of Pro. |
| Features | AUp to 30 sets of sites, each with its own days and times, blocked in fixed periods, after a time limit, or both. Lockdown blocks right now, a delay page makes you wait, and a password or random access code guards the settings. Wildcards and keywords work too. For a site blocker, that's deep. | AA Pomodoro timer with lengths you can change, sites blocked while a session runs, blocking on a schedule, and Autoblock, which counts down before shutting a site. Name a session and it becomes a task timer with a to-do list. Focus and distraction analytics round it off. |
| Ease of use | BIt's an extension, so there's no App Store rating to go on and a B is as far as we'll go. It installs into the browser you already use. With this many options, expect to spend a while in the settings. | BIt's an extension, so there's no App Store rating to go on and a B is as far as we'll go. Sites go on the blocklist in one click, and you can unblock one for a moment when you need it. |
| Platforms and integrations | CA browser extension for Firefox, Chrome, Edge and other Chromium-based browsers, and nothing else. There's no macOS or iOS version: the site points to ivBlock, a separate product, for those. No integrations are listed. | CA Chrome extension, plus a web version that's a plain timer without blocking. There's no desktop or mobile app, and the vendor gives no date for the mobile app on its roadmap. No integrations are listed. |
| Best for | free, fine-grained site blocking in your browser | a Pomodoro timer and site blocker in one Chrome extension |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: LeechBlock NG and Otto. How we grade
Where they differ
- LeechBlock NG is free. Otto starts at $29 for a one-year license, or $66 once for a lifetime license.
- Only Otto lists a web app.
- LeechBlock NG is open source, according to its own site.
- Otto can be bought with a one-time purchase.
- Otto also covers tasks, Pomodoro timer and time tracking.
In commonFree planBrowser extensionSite & app blocker
At a glance
| LeechBlock NG | Otto | |
|---|---|---|
| Pricing | Free | Free plan |
| Starts at | Free | $29 for a one-year license, or $66 once for a lifetime license |
| Free plan | Entirely free: the site calls it a simple free productivity tool and lists no paid version. The source code is on GitHub under the MPL-2.0 license. | Unlimited focus sessions, 4 focus block rules, 2 scheduled blocking rules, 2 specific-URL rules, 1 autoblock rule, 3 tasks of 15 minutes and 7 days of analytics. |
| Free trial | None listed | None listed |
| Web | ||
| Browser extension | ||
| Made by | James N. Anderson | Layover Studio LLC |
| Price read from | proginosko.com | ottoapp.me |
| Checked | Oct 6, 2026 | Oct 9, 2026 |
Who each one suits
LeechBlock NG
- People who want a free site blocker inside the browser they already use
- Rationing a site by time allowance rather than blocking it outright
- Users who want fine control with wildcards, keywords and regular expressions
Otto
- People who do most of their work inside Chrome
- A Pomodoro timer and a site blocker in a single extension
- Buyers who prefer a lifetime license to a subscription
- People who want a gentle, game-like nudge instead of a hard lockout
Worth knowing
LeechBlock NG
- It blocks only inside the browser where it is installed; other browsers and desktop apps are unaffected.
- The developer says it is not designed for parental control or for blocking offensive content.
- There is no macOS or iOS version; the site points to ivBlock, a separate product based on LeechBlock.
- The browser may still connect briefly to a blocked site, so the developer suggests a HOSTS-level blocker when no connection at all is wanted.
Otto
- It is a Chrome extension: there is no desktop or mobile app, and the vendor gives no date for the mobile app on its roadmap.
- The free version caps scheduled blocking at 2 rules, autoblock at 1 rule, the task timer at 3 tasks of 15 minutes and analytics at 7 days.
- The one-year license does not carry on: when it expires, Pro features stop and the extension drops back to the free version.
- There is no free trial of Pro, though refunds are given within 14 days. The web version is a plain timer without blocking.
Key features
LeechBlock NG
- Block sets
- Up to 30 sets of sites, each with its own list, days and times. Lists accept wildcards, exceptions and keywords that match words in a page's title or text.
- Time periods and time limits
- Block within fixed periods such as 9am to 5pm, after a time limit such as 10 minutes in every hour, or with both combined. Unused time can roll over to the next period.
- Lockdown
- Blocks the sites in chosen block sets immediately for a duration you specify, outside their normal schedule.
- Delaying and password pages
- Instead of a plain block, a page can show a countdown before letting you through or ask for a password. A custom blocking page can also be set by URL.
- Access control
- A password or a random access code can guard the options page, to slow down any attempt to change settings in a weak moment.
- Temporary override
- An optional override lifts blocks for a set number of minutes, with a cap on how many overrides are allowed in an hour, day or week.
Otto
- Pomodoro focus timer
- Work and break intervals with lengths you can change and no cap on sessions. Pro adds a reverse work and break timer and a strict lock on the timer.
- Blocking during focus sessions
- Sites on the blocklist are blocked whenever a work session is running. Sites can be added in one click and unblocked temporarily when you need them.
- Scheduled blocking
- Chosen sites can be blocked at set hours and on set weekdays without a focus session running, and rules can target specific URLs instead of a whole site.
- Autoblock time limits
- Instead of blocking a site at once, Autoblock starts a countdown and blocks it when the time runs out. Each rule has its own duration and the count syncs between tabs.
- Task timer
- Naming a session turns it into a task timer with an in-browser to-do list, single-task and sequence modes, and a record of the time spent on each task.
- Analytics and the Otto character
- Focus and distraction analytics cover 7 days on the free version and all time on Pro. A game mechanic builds a bond with the Otto character as you focus.
Plans
LeechBlock NG
LeechBlock NG$0
The complete extension: up to 30 block sets, time periods and time limits, lockdown, delaying and password pages, and access controls.
Otto
Free$0
Unlimited focus sessions, 4 focus block rules, 2 scheduled blocking rules, 1 autoblock rule, a 3-task timer and 7 days of analytics.
The Friend$29
for one year, paid once (not a subscription)
Otto Pro for a year: unlimited blocked sites, schedules and autoblock rules, tasks of up to 90 minutes, strict lock and all-time analytics.
The Guardian$66
one-time purchase, lifetime license
The same Pro features with a license that never expires, free lifetime updates and the planned mobile app at no extra cost.
Ways to pay less
LeechBlock NG
No public discounts listed.
Otto
- Lifetime license
Lifetime license for a one-time $66
The Guardian plan unlocks every Pro feature for good for a single $66 payment, against $29 for one year, and includes the mobile app once it is released.
