Solid block



Solid blocks consist of any type of block that has a collision block that players, mobs, or other entities cannot move through.

Properties
A block can be considered solid if it has a collision box that players, mobs, or other entities cannot move through. For a block to be solid it also has to not be broken by flowing liquids. Blocks such as iron blocks are solid, and cobwebs are non-solid, because players can move through them slowly and water flow can break them.

The collision property of solid blocks allows block-dependent blocks and entities to be placed upon them, including:



Other block-dependent blocks may be placed only on full, opaque solid blocks (with a few exceptions):



Solid blocks are also considered when generating structures.

List of solid blocks
The following blocks are all solid blocks. They are categorized by their material.

List of non-solid blocks
These blocks consist of any block that is not solid.

Height
Most solid blocks are 1 meter high, but certain blocks have non-standard block heights.

A player can automatically step up from a lower to a higher height, if the difference is at most 0.6 ($3/5$) of a block. From ground level, this is anything the height of a chain or less.

A player can fit through spaces as small as 1.8125 (2 - $3/16$) blocks high, since players are 1.8 blocks tall. This allows players to fit through a 2-block gap with a floor as high as a trapdoor.

When, a player can fit through spaces as small as 1.75 (2 - $1/4$) blocks high, or 1.5 blocks, since sneaking players are 1.65 blocks or 1.5 blocks tall, respectively. In Bedrock, this allows players to fit through a 2-block gap with a floor as high as 3 layers of snow. In Java, players can fit through a 2-block space with a floor as high as a slab.

When gliding with elytra, a player can fit through spaces as small as 0.625 (1 - $3/8$) blocks high, since gliding players are 0.6 blocks tall. This allows players to fit through a 1-block gap with a floor as high as 4 layers of snow, or a flower pot, or a daylight sensor.

Note that doors, although appearing to be one 2-meter-high block, are actually composed of two (top and bottom) 1-meter-high blocks.

Here is a list of blocks with non-standard heights, from tallest to shortest in height: