Tofugu's Japanese Grammar lets you look up specific Japanese grammar points. You can either look for grammar constructions by selecting related categories such as "Verb Conjugation" and "い-Adjectives," or use a search bar that allows you to find constructions you are interested in.
Individual grammar entries provide an in-depth explanation, plenty of example sentences, warnings regarding common mistakes, and references. What makes Tofugu's grammar guide stand out is that it often conceptualizes grammar points. For example, the particle に is taught as something like a pin on a map. And as you read on, you get to learn how the に particle works like a pin — being used to pinpoint a location, a spot that something gets attached to, or a point in time. With this approach, it is easy to understand and make connections with different uses of a grammar point that are seemingly unrelated to each other, rather than trying to cram everything into your brain.
On each page, the content is organized into "The Basics" and "Beyond The Basics" parts, which makes it easy to know what's essential and what's advanced information. It also provides patterns of usage, and then gives a number of different contexts in which one could use each pattern. There are plenty of example sentences, and the content is quite understandable overall.
While there are currently not as many constructions as in other grammar guides, Tofugu's Japanese Grammar is continuously being updated and added to.