Luminance

Lighting affects visibility, Mob spawning, tree growth, and whether flowers and mushrooms will stay planted. Lighting can be provided by sunlight, torches, fire, lava, in-use furnaces, and certain other objects.

Light-emitting blocks

File:LightEmittingBlocks.png

Blocks that emit light

The following values are the brightness of the block itself. The light emitted decreases by one for each square of distance from the light source. Glass does not diminish the light that passes through it, but water or ice reduces light that passes through it by 3 (2 for passing through +1 for normal block decrease). In Minecraft's source code, the luminescences are defined using the floating point values in the third column. In a weird quirk, these floating point numbers are fractions of 16, but are multiplied by 15 to get the integer light value. This means that both 0/16 and 1/16 (0.0 and 0.0625) correspond to the integer light value 0.

Icon	Block	Light Level	Data Value
	(Sunlight)	15	1.0F
	Fire
	Jack-O-Lantern
	Lava
	Glowstone
	Locked Chest
	End Portal Block
	Redstone Lamp, when active
	Torch	14	0.9375F
	Lit Furnace	13	0.875F
	(Sunlight, when raining or snowing)	12	0.8125F
	Nether Portal Block	11	0.75F
	(Sunlight, when thundering)	10	0.6875F
	Redstone Ore, when touched	9	0.625F
File:Redstone (Repeater, Active).png	Redstone Repeater, when active
	Lit Redstone Torch	7	0.5F
	(Moonlight)	4	0.3125F
	Brown Mushroom	1	0.125F
File:Brewing Stand.png	Brewing Stand
	Dragon Egg

• There is currently a bug where naturally generated Torches in Abandoned Mineshafts, Strongholds, or NPC Villages and Glowstone in The Nether do not always emit light and remain dark until there is a lighting update.