Simply blocks all distractions given you have a bit of discipline. I recently got depressed because of reading news daily. I blocked all related pages on my PC and my Android phone. It just works, but might need a slight learning curve.

One of the best extensions you will ever install. Simple and easy to use, it's by far the best browser blocking add-on out there. Even just a 30 second time-out (you can chose the time) before letting you waste time on Twitter or wherever, is enough for you to dosconnect from mindless-browsing-brain and make a conscious choice about whether that is really what you need to do. Most of the time it isn't and you will close that tab immediately, but when you really do need to go to a time-suck site, you still can without too much interruption.

This is great. I can use lots of customization.

Is there any way to get a dark background for the block page??

Perfect for keeping myself productive

A game changer for productivity. It's surprisingly robust, and only a little buggy! But that's OK considering that the extension is FREE and without ads. Give yourself some times to thoroughly inspect all the options and figure out how you can use them. You might think something isn't working, but maybe you haven't looked over your settings well? This feels more like a tool than an extension, which is fantastic and worth it for anybody who does serious work on their PCs.

Excelente

Effective and easy to use. I cannot recommend this highly enough.

Good stuff, mes amis

It was working amazing till today, when it gave me access to a blocked site again(I generally tried to open the site when I got distracted, saw that leechblock blocked it, and went back to working.). I went into lockdown and manually locked down for 100 hours and it locked the site down again. I don't know how it gave me access to that site though.

Firefox 68 user here. Leechblock rating reduced to 3 stars; stops working, does not block URLs reliably. This used to be a stable and VERY useful extension, but now (Sep 2019) it stops working altogethter every few weeks (fails to block any of my specified URLs). Removing the extension and re-installing sometimes fixes the issue, but only temporarily. Hopefully a future extension or Firefox update will fix the bug causing LeechBlock to suddenly stop working entirely.