Nether Portal

{
 "title": "Nether Portal",
 "rows": [
 {
 "field": "Yes, only when an entity goes through a portal and there is no other active portal within 128 blocks of the matching coordinate",
 "label": "Generates in<br>existing chunks  "
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 {
 "field": "\n* <span class=\"nowrap\"><span class=\"sprite-file\" style=\"\">(link to File:BlockSprite obsidian.png article, displayed as 16x16px|link=Obsidian|alt=|class=pixel-image|)</span>(link to Obsidian article, displayed as <span class=\"sprite-text\">Obsidian</span>)</span>\n* <span class=\"nowrap\"><span class=\"sprite-file\" style=\"\">(link to File:BlockSprite nether-portal.png article, displayed as 16x16px|link=Nether Portal (block)|alt=|class=pixel-image|)</span>(link to Nether Portal (block) article, displayed as <span class=\"sprite-text\">Nether Portal</span>)</span>",
 "label": "Consists of"
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 "invimages": [],
 "images": [
 "Nether portal.gif"
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}

The Nether portal is a manufactured structure made of obsidian that acts as a gateway between the Overworld and the Nether dimensions.

The Nether portal is built as a vertical, rectangular frame of obsidian (4×5 minimum, 23×23 maximum). The four corners of the frame are not required, but portals created by the game always include them, resulting in 4 free/extra obsidian. The obsidian can be placed in any manner, e.g. by placing mined obsidian, by completing a ruined portal, or by casting it in place using lava and water. Adjacent portals can share obsidian blocks. A Nether portal cannot be built horizontally like an end portal.

Once a frame is constructed, it is activated by fire placed inside the frame. This creates portal blocks inside the frame, resembling a vortex. The fire can be placed in any manner, including use of flint and steel or a fire charge, the impact of a fireball or small fireball, a lightning strike, or natural spread of fire to flammable material adjacent to the portal. Nether portals can be activated only in the Overworld or the Nether; they cannot be activated in the End and custom dimensions.

The fire must be the last placed block in the structure—a fire on an incomplete frame does not result in the portal activating upon the placement of the last obsidian block.

If no corresponding portal within range exists in the other dimension when a portal is used by almost any entity except withers and the ender dragon‌^{[Java Edition only]} or by a player‌^{[Bedrock Edition only]}, one is created there; see § Portal search and § Portal creation.

When a player in the Overworld or the Nether stands in a Nether portal block for 80 game ticks (4 seconds) in survival mode or 1 game tick (¹⁄₂₀ second) in creative mode, the player is taken to the other dimension (In Java Edition, the teleport delay can be configured by changing the gamerule playersNetherPortalDefaultDelay and playersNetherPortalCreativeDelay for players in Creative Mode). The player can step out of a portal before it completes its animation to abort the teleport. If there is already an active portal within range (about 128 blocks) in the other dimension, the player appears in that portal. Otherwise, a portal is created at or near the corresponding coordinates. If a portal is deactivated, and the matching portal in the other dimension is used before it is re-activated, a new portal may be created (unless there is another active portal within range). The usual cause for this is when the player's Nether-side portal is deactivated by a ghast, and then the player dies in the Nether, spawns, and then re-enters the Nether through the Overworld-side portal. However, multiple portals can be exploited to farm obsidian.

Most entities can travel through portals, including mobs (except the wither and ender dragon), thrown items, and transportation with passengers‌^{[Java Edition only]}, including boats, minecarts and horses. Unlike players, other entities travel through portals instantly, and once they reach the other side, there is a cool-down time for 300 game ticks (15 seconds), in which they cannot go through any Nether portals. Therefore, an entity can travel though Nether portals again after not touching any Nether portal for 15 seconds. An exception are minecarts and boats, which have a 10 tick (0.5 seconds) cooldown. In Bedrock Edition, a parrot on the player's shoulder prevents the player from going through the portal.^[1]

Another exception is an entity ridden by a player, the whole assemblage of which has the unusual combination of instant travel as well as no cooldown.^{[verify for Bedrock Edition]}

Zombified piglins have a chance​^{[more information needed]} to spawn on the bottom frame of the portal in the Overworld in Java Edition if any Nether portal block above receives a block tick. In Bedrock Edition they spawn in certain squares adjacent to the portals in the Overworld, not inside them. Zombified piglins spawned in this way have a full 15-second portal cooldown, meaning they can't go through the portal they are spawned in unless they leave the portal for a while. They spawn twice as often on Normal difficulty as on Easy, and three times as often on Hard difficulty as on Easy. No other mobs can be spawned by Nether portals in this way, in any dimension.

Active portals also repel hoglins.

Whenever an entity is teleported through a Nether portal, the chunk at the linked portal gets load ticked with load level of 30, meaning that it is fully loaded and can process entities. This load level also spreads to adjacent chunks but they get lower for each chunk. This results in 8 more fully loaded "entity ticking" chunks with gradually fewer loaded chunks further out.

These chunks remain loaded for 15 seconds but this timer gets refreshed each time the entity passes through the portal (including mobs wandering through it from either direction). This can be used to permanently load chunks, creating a "chunk loader". Permanently-loaded chunks created using chunk loaders create a measurable amount of lag.^{[citation needed]}

Horizontal coordinates and distances in the Nether are proportional to the Overworld in a 1:8 ratio. That is, by moving 1 block horizontally in the Nether, players have moved the equivalent of 8 blocks on the Overworld. This does not apply to the Y-axis. Thus, for a given location (X, Y, Z) in the Overworld, the corresponding coordinates in the Nether are (floor(X ÷ 8), Y, floor(Z ÷ 8)), and conversely, for a location (X, Y, Z) in the Nether, the matching Overworld coordinates are (X × 8, Y, Z × 8).

The Java floor() method used in these conversions rounds down to the largest integer less than or equal to the argument (toward smaller positive values and toward larger negative values), so a coordinate of 29.9 rounds to 29, and one of −29.9 to −30.

Both the X and Z coordinates in this conversion are constrained to be within the world border (29,999,983 and -29,999,984 (inclusive)); this affects travel to the Overworld from the Nether at X or Z beyond ±3,749,998.

When an entity starts colliding with a Nether portal block, the game records the coordinates of the entity.

The game then converts those coordinates into destination coordinates as above: The entry X- and Z-coordinates are multiplied by 8 if the entity is in the Nether or divided by 8 if the entity is in the Overworld, while the Y-coordinate is not changed.

Starting at these destination coordinates, the game looks for all nearby portal points of interest. The point of interest can be within a 256×256 square block area (128-block radius) in the Overworld and a 32×32 square block area (16-block radius) in the Nether^[2] centered on the converted coordinate and the full map height.

If any candidate portal point of interest is found, then the game selects the closest one as determined by its distance in the new coordinate system (including the Y coordinate, which can cause seemingly more distant portals to be selected), and teleports the entity to the location in the new portal calculated by a special algorithm. Note that the calculated distance is Euclidean distance, not taxicab distance. The distance computation between portals in the range is a straight-line distance calculation, and the shortest path is chosen, counting the Y difference.

The algorithm used for determining the position of the entity inside the destination portal to teleport to is as follows:

• Portal rectangle dimensions are determined for both source and destination portals. (Not counting the obsidian)
• Entity hitbox dimensions are subtracted from those rectangles' width and height, meaning that the entity can now be considered as a point, to avoid problems with preserving the hitbox dimensions in a geometrical transformation.
• Distance between the bottom of the source portal and the bottom of the entity hitbox is measured, similar is done for distance to one of the sides of the portal.
• Those offsets are then multiplied by the ratio of the reduced sizes of the portals and used to get the position in the destination portal.
• If one of the dimensions of entity hitbox is larger than the portal, the corresponing dimension falls back to bottom-middle of the destination portal, the other dimension is still calculated using the algorithm.
• If the destination portal is at 90° to the source portal, entity yaw and velocity are rotated 90° clockwise, regardless of the direction of travel, meaning that if player travels there and back without touching their mouse, they get rotated 180°, but the coordinates remain the same, making it appear as if the player exited through the wrong side of the portal ‌^{[Java Edition only]}.

This way, if source and destination portals are of the same shape, have the same orientation, and no other portals are interfering with the linking, one can safely assume that entities can travel through them as if the portal frames were physically placed behind each other.

If no portals exist in the search region, the game creates a new one by looking for the closest suitable location to place a portal, within 16 blocks horizontally (but any distance vertically) of the incoming entity's destination coordinates. A valid location consists of 3×4 buildable blocks​^{[more information needed]} with 4 blocks of air above all 12 blocks, with the long axis matching the long axis of the source portal. The closest valid position in the 3D distance is always picked. The incoming entity can be almost any entity except withers and the ender dragon in Java Edition or only be a player in Bedrock Edition.

This means that if a portal constructed in the Nether exceeds 18 blocks wide, each end will connect to two separate Overworld portals.

If the first check for valid locations fails entirely, the check is redone looking for a 1×4 expanse of buildable blocks with air 4 high above each.

If that fails, too, a portal is forced at the target coordinates, but with Y constrained to be between 70 and 10 less than the world height (i.e. 118 for the Nether or 310 for the Overworld). When a portal is forced in this way, a 2×3 platform of obsidian with air 3 high above is created at the target location, overwriting whatever might be there. This provides air space underground or a small platform if floating. In Bedrock Edition, these obsidian blocks are flanked by 4 more blocks of netherrack on each side, which is the only renewable source of netherrack.

Once coordinates are chosen, a portal (always 4×5 and including the corners) including portal blocks is constructed at the target coordinates, replacing anything in the way.

If a portal is forced into water or lava, the liquid immediately flows into the generated air blocks, leaving the player with no airspace. However, a glitch can prevent this water from flowing into the portal: if the liquid would flow both vertically and horizontally into the air pocket, it instead flows only vertically, so the blocks on the platform's outer corners never become water source blocks.

Java Edition

Bedrock Edition:

Issues relating to "Nether Portal" are maintained on the bug tracker. Issues should be reported and viewed there.

• Portals can be placed together in a tunnel-like fashion, though it appears as if the third portal is lit as the first two in a row mimic glass. If more than six portals are connected, the inner portals are completely invisible while in the portal tunnel; however, the particle effects can still be seen throughout. These connected portals also share the 4-second countdown until teleportation, so as long as the player is within a connected portal, they are sent to another dimension.
• The player cannot open their inventory while standing in an active portal, and any other GUI (such as that of a chest or villager) is immediately closed when opened.
• If two portals intersect and the player lights a fire in the intersection (i.e., in both portals at once), only the portal that lies within the x-axis is activated. Lighting any other block activates whichever portal it is in.
• Minecraft's "Visit the Nether!" describes the portal surface as "a translucent, purple, liquid-like substance."^[9]
• Nether portals can theoretically spawn pre-lit, if two ruined portals or a ruined portal and one of the rooms with obsidian of a woodland mansion intersect so that a complete obsidian frame is formed, and fire spreads into the middle of the frame through natural means.

• A LEGO Minecraft Nether portal was included in the LEGO Minecraft Set: "The Nether".
• On 29 October 2010, PC Gamer released this video, showing a portal being constructed and used.
• On 1 April 2011, Think Geek released this video to advertise one of their annual fake April Fools products: the Minecraft USB Desktop Nether Portal.

• 👁 A zombified piglin wandered through a Nether portal and into the Overworld.
  
  A zombified piglin wandered through a Nether portal and into the Overworld.
• 👁 A view of inside a portal.
  
  A view of inside a portal.
• 👁 The biggest Nether portal size (23×23 exterior, 21×21 opening).
  
  The biggest Nether portal size (23×23 exterior, 21×21 opening).
• 👁 Nether portal generated on a cliff in crimson forest.
  
  Nether portal generated on a cliff in crimson forest.
• 👁 A cluster of Nether portal frames generated by repeatedly going through the Nether-side portal, deactivating the Overworld-side portal and teleporting back to the Nether.
  
  A cluster of Nether portal frames generated by repeatedly going through the Nether-side portal, deactivating the Overworld-side portal and teleporting back to the Nether.

• 👁 Ari and Noor entering into a Nether portal.
  
  Ari and Noor entering into a Nether portal.
• 👁 Efe failing to construct a Nether portal
  
  Efe failing to construct a Nether portal

• 👁 Screenshot of a lit Nether portal during a1.2.0-preview.
  
  Screenshot of a lit Nether portal during a1.2.0-preview.
• 👁 Image released for 1.7.2 by Dinnerbone on September 11, 2013
  
  Image released for 1.7.2 by Dinnerbone on September 11, 2013
• 👁 7×7 portal.
  
  7×7 portal.
• 👁 Large Portal.
  
  Large Portal.
• 👁 A large Nether portal.
  
  A large Nether portal.
• 👁 Darngeek standing in front of a Nether portal.
  
  Darngeek standing in front of a Nether portal.
• 👁 Two Nether portals next to each other.
  
  Two Nether portals next to each other.
• 👁 Screenshot from Searge showing a 3×4 Nether portal.
  
  Screenshot from Searge showing a 3×4 Nether portal.

• 👁 A Nether portal in a mangrove swamp, as shown in the Wild Update trailer.
  
  A Nether portal in a mangrove swamp, as shown in the Wild Update trailer.
• 👁 A snifflet wandering into a Nether portal.
  
  A snifflet wandering into a Nether portal.
• 👁 A Nether portal in the jungle.[10]
  
  A Nether portal in the jungle.^[10]
• 👁 A camel peeking out of a portal.
  
  A camel peeking out of a portal.
• 👁 A Nether portal as it appears in the Minecraft Legends Live Event.
  
  A Nether portal as it appears in the Minecraft Legends Live Event.
• 👁 An officially licensed "Nether Portal Glitter Motion Light."
  
  An officially licensed "Nether Portal Glitter Motion Light."
• 👁 Official artwork featuring a Nether portal.
  
  Official artwork featuring a Nether portal.
• 👁 Official artwork featuring multiple Nether portals.
  
  Official artwork featuring multiple Nether portals.
• 👁 Official artwork featuring a nether portal.
  
  Official artwork featuring a nether portal.
• 👁 Official artwork featuring a nether portal.
  
  Official artwork featuring a nether portal.
• 👁 Pixel art of Zuri leaping out of a portal, featured on Minecraft.net.[11]
  
  Pixel art of Zuri leaping out of a portal, featured on Minecraft.net.^[11]
• 👁 A nether portal in A Minecraft Movie.
  
  A nether portal in A Minecraft Movie.
• 👁 A nether portal as it appears in Minecraft: Woodsword Chronicles
  
  A nether portal as it appears in Minecraft: Woodsword Chronicles