|This feature is exclusive to Java Edition.|
The world boundary is the area at the edge of the Minecraft world.
The boundary of the world has several "layers".
The first layer is the world border, which lies at X/Z ±29,999,984 by default, and establishes an arbitrary blockade to prevent the player from advancing. There are several methods of bypassing this border.
The second layer lies exactly one chunk further, at X/Z: ±30,000,000. At this point, there is an invisible wall preventing the player from advancing, even in spectator mode. Using commands like
/teleport does not work, since the game does not accept any value beyond X/Z: ±30,000,000. Other block interactions, such as TNT exploding or water flowing, will affect blocks outside this limit. By using a minecart (in a superflat preset with the top layer as rails), the player can go even further, up to X/Z: ±30,000,496. At that point, the player is frozen in place until the minecart is destroyed, then they are teleported back to X/Z: ±30,000,000.
The third and final layer lies at X/Z: ±30,000,496, which can be considered the absolute edge of the Minecraft world, as chunks no longer generate beyond this point. This value is hard-coded into the game's source code, so it's impossible to advance past this point without the use of modifications.
The maximum possible height is 1.798×10308 (or 21024), the limit where mathematics break down in the game's code. In attempting to teleport beyond this limit, the game interprets the number as infinity and refuses to carry out the teleportation.
By editing the source code for the game, it is possible to extend the terrain generation and world border past X/Z: ±30,000,240 (up to X/Z: ±2,147,483,647) and experience the game quite normally (no ghost chunks; mobs can spawn alright; commands accept higher values). The game performs normally even at distances of X/Z: ±1,000,000,000. At greater distances, block lag starts to become noticeable, and mobs begin behaving very strangely. A hard limit exists at X/Z: ±2,147,483,647—the mathematical limit of a signed 32-bit integer—and attempting to travel or load chunks near here simply causes the game to crash. It is advisable to set the world border to at most several hundred blocks before this limit. Lighting ceases to work past 225 and everything becomes absolutely dark unless with the night vision effect. Entering a nether portal at this point would teleport the player to X/Z ±268,435,455 in the nether.
- Gravity-affected blocks (such as sand and gravel), while falling, jitter in bizarre patterns for several seconds, but ultimately land on the ground as normal.
- Water and lava fall normally, albeit at a much slower pace due to long response times.
- Extended pistons may sometimes not render until they receive another block update.
- Flame and smoke particles from certain blocks, like monster spawners and end portals, only appear on the side facing away from the edge. Flame particles still appear around the entire mob spawner block as a mob is spawning.
- Beyond the X/Z 30,000,000 mark:
|Java Edition Indev|
|?||Beyond the edge of the world, many glitches occur when the player travels thousands or millions of blocks away from the origin. At X/Z: ±8,388,608, blocks are no longer solid, allowing the player to fall forever from this point.|
|Java Edition Infdev|
|20100227||There are many limits to the game that can occur when traveling millions of blocks away, but beyond X/Z: ±16,777,216, blocks are no longer solid and the player can fall into the layer of lava that is below the world in these versions.|
|A large stone wall generates at and past 33554432.|
|20100327||Blocks beyond X/Z: ±32,000,000 do not generate. A player who tries to walk over the edge gets stuck in a glitched position forever.|
|Java Edition Alpha|
|v1.2.0||?||"Fake Chunks" (where chunks of bare terrain render, but physics do not function properly) now appear beyond X/Z ±32,000,000 and blocks are not solid, hence the player can now fall through the world.|
|Java Edition Beta|
|1.8||?||The Far Lands phenomenons was removed, as an unintended side effect of the large changes in the terrain generator.|
|The "fake chunks" now start at X/Z: 30,000,000, 2 million meters less than in Alpha v1.2.0 - Beta 1.7.3.|
|1.8.1||release||Using an NBT editor, beyond X/Z: 30,000,032, the player gets stuck in a glitched position and need to use a program to make their character back. Beyond X/Z: 30,000,064, blocks no longer render. The map is blank from here on out. At every power of two beyond here, rain generates in a line (if only on one axis) and is separated by larger and larger gaps. At X/Z: 2,147,483,512, blocks stop generating. Beyond X/Z: 25,769,804,000, the clouds no longer render. Beyond X/Z: 34,359,738,368 the game crashes due to chunks being overwritten.|
|1.0.0||?||Many lighting glitches and strange air pockets form on multiplayer, although untested in singleplayer.|
|1.7.2||13w36b||Minecraft crashes after X/Z: ±29,999,840 on Default, Large Biomes, and AMPLIFIED worlds.|
|13w37a||There is an invisible wall at X/Z: ±30,000,000 that goes up to Y: 2,147,483,647. Walking on this wall far enough causes the game to crash.|
|All blocks (including air) within the invisible wall act as solid blocks. Because of this, if a player is moved outside the boundary via commands or external tools, they become immobile.|
|Beyond the invisible wall, if items are thrown, the falling animation is jittery. The thrown item disappears upon contact with any block other than air.|
|Beyond X/Z: ±32,000,000, the player is kicked out with an "Illegal Position" message.|
|Some mobs (e.g. slimes) try to go past the world border, to no avail.|
|1.8||?||The invisible wall was replaced with a proper world border, removing a large portion of the effects of the world boundary.|
|Fake chunks beyond the world border no longer render, instead they give way to the Void.|
|Beyond X/Z: ±30,000,000, the game freezes. Any players who attempt to go any further are kicked by the server, with the message "Illegal Position". The only way to fix this is to move the player back to a previous position through the use of external programs.|
|1.8.2||pre4||The game no longer kicks the player for attempting to teleport beyond the world border, nor does the game freeze. However, the generated world does appear to become increasingly barren towards X/Z: ±30,000,000, and dropped items begin to 'clump' together in certain places.|
|1.9||?||Teleporting past X/Z: ±30,000,000 is no longer possible; the player always gets teleported to X/Z: ±30,000,000, even when using external programs.|
|Chunks beyond X/Z; ±30,000,000 are now rendered again, until X/Z: ±30,000,240. Many of the issues surrounding block and item rendering have also disappeared; with this, the world boundary is now generally more stable. Also, the chunks beyond X/Z: ±30,000,000 are now solid and can perfectly generate structures like villages, mineshafts, and trees.|
|1.14||?||Light no longer exists past 33554432.|
Though the reason for the world boundary is still controversial, it may have to do with the way Minecraft generates and loads chunks in the game. When the game generates its terrain, it uses something called 3D Perlin Noise. This is a noise map that shows how high or low Minecraft blocks generate. When the game generates the terrain, it creates a noise map of all the terrain that cannot be interacted with at all. Then, Minecraft would load in the chunks after the basic frame was in place. When the game generates chunks out to X/Z: 30,000,000, for some reason the game cannot load chunks beyond this point. However, the terrain noise map has generated the terrain all the way out to X/Z: 2,147,483,647. So Minecraft still generates the terrain noise map, but not the blocks themselves. So what we get is empty terrain that has the textures for the terrain that should be there.
- Traveling from one edge of the world to the opposite edge by powered rail would take 35 days and 10 hours. Building the rails for such a trip would require enough iron and/or gold to fill over 723 double chests, even when packed into blocks, as well as sticks made from enough wood to fill over 135 double chests (as log blocks, not as planks, and excluding the redstone torches). (53 stacks of logs would be required just to make enough chests to hold all the building materials for this rail track.) If already crafted, the rails required would fill 17,361 double chests. If the player had to gather the materials to make all those rails, they would wear out 14,404 diamond pickaxes and 300 diamond axes (on average, about 3,601 diamond pickaxes and 75 diamond axes, both enchanted with Unbreaking 3).
- Even if one were to amass all these materials, actually laying said track would require the player to travel the entire distance through other means anyway.
- Factoring in the need for powering the track and assuming the player were to use redstone torches, the player would require 3,529,412 torches for the full track, since a torch can optimally light 17 blocks. That requires 55,148 sticks and bits of redstone dust, which requires 2042 large chests, which requires 128 stacks of log blocks to make the chests (which requires 3 large chests).
- It is possible to generate trees and vegetation beyond 30,000,000 by loading a version of Minecraft after Java Edition 1.9, then load a few chunks beyond the world border. Then, close the world and load a version of Minecraft between Beta 1.8 - Release Java Edition 1.6-pre and load the same world. If the players travel to the world barrier, there are a few chunks that generate beyond 30,000,000 that have trees and grass.
- It is possible to even generate Far Lands chunks using this method. Load a world in release Beta 1.8 - Release 1.6 and teleport to X/Z: 30,000,000. Close the world before the fake chunks generate and load the world in Beta 1.7.3. The Far Lands chunks load and then, the player can load as many chunks as they want. Then close the world and load it in a newer version, and the player has Far Lands chunks in the 30,000,000 block area.
- Spiders can climb the border, continuing to climb upward indefinitely.