{{for|other uses|Seed (disambiguation)}}
'''Seeds''' are values made up of character(s) (including negative or positive integers) that are used as the basis for [[world generation|generating every ''Minecraft'' world]].<ref>[https://web.archive.org/web/20120307165955/https://www.mojang.com/2011/02/a-short-demystification-of-the-map-seed/ A Short Demystification of the 'Map Seed'] - Jens Bergensten on Mojang.com; February 23, 2011</ref>

== Compatibility ==
Seeds are somewhat compatible across editions, with terrain generation and biomes being the same. However, the placement of generated [[structure]]s differs between ''[[Java Edition]]'' and ''[[Bedrock Edition]]''.

== World generation ==
{{main|World generation}}

Whenever the game has to generate a new world, it calls upon an algorithm known as ''{{w|Perlin noise}}''. This algorithm outputs a pseudo-random value that is then used to determine the characteristics and features of the world. However, the algorithm always outputs the same value each time for a constant starting point (seed). Thus, the same seed generates the same terrain every time.

A world's seed is set when that world is created. By default, it is decided automatically, but it can also be set manually. Setting and reusing a seed from one world generates the same world. Either a number or a word/phrase can be used, including negatives. If a word/phrase is used, it is converted into a 32-bit integer.

Whenever the world generation algorithm is updated (usually by adding new biomes to the game), the same seed no longer generates the same terrain. If the seed or generator changes in a saved world, new [[chunks]] are based on the new seed and no longer match those from the old seed. Deleted chunks can regenerate if the seed and generator remain the same, but changes if either the seed or generator changes. In fact, deleting chunks is sometimes done to let newly-introduced features appear in an old world; see [[Tutorials/Updating old oceans in 1.13 using MCEdit]].

Because seeds are simply random values read into an algorithm and not actually names of different worlds, using a certain seed does not result in a world with any relevance to the value of that seed. For instance, using a [[biome]] name as the seed does not necessarily result in the creation of a world with primarily that biome, nor does it spawn the player within the said biome.

{{Calculator|seedHashcode}}

== Determining the seed ==
{{IN|java}}, the player can enter the [[command]] {{command|seed}} to view the world's seed. This command is available in singleplayer worlds even if cheats are off. The player can also select 'Re-create' in the Worlds menu to see the seed.

{{IN|bedrock}}, the seed can be found on the world options screen. There are also [[seed templates]] that offers the player several pre-set seeds to generate worlds with specific features near the spawn point. Additionally, the beta version has a visible seed on the top of the screen.

== Notable seeds ==
The following map seeds have, at one point or another, been used for generating official ''Minecraft'' maps and resources or otherwise significant community material.

* The ''Java Edition'' demo world seed can be played in the full version by entering {{cd|North Carolina}} in the seed input.
* The PC Gamer demo world seed can be played in the appropriate era by entering {{cd|glacier}}, all lowercase unlike the famous seed where the G is capitalized, in the seed input.
* The seed for each [[Title Screen|title screen]] [[panorama]] are as follows:
**The panorama used between [[Java Edition Beta 1.8 Pre-release|Beta 1.8 Pre-release]] and [[Java Edition 18w22c|18w22c]] is either {{cd|2151901553968352745}} or {{cd|8091867987493326313}},<ref>https://www.reddit.com/r/Minecraft/comments/hthrmk/big_news_we_have_found_the_seed_of_minecrafts/</ref> generated between [[Java Edition Beta 1.6.6|Beta 1.6.6]] and [[Java Edition Beta 1.7|Beta 1.7]].
** Bedrock Edition 1.2.0 is {{cd|95475027}}, which is the same seed as the "Winding River" [[seed template]] generated before [[Bedrock Edition 1.18.0|1.18.0]].
** Java Edition 1.13 is {{cd|1458140401}}, which is the seed resulting from typing {{cd|18w22a}} in as a seed, generated in snapshot [[18w22a]].
** Java Edition 1.14 is {{cd|2802867088795589976}}, taken in [[18w48a]].
** Java Edition 1.15 is {{cd|-4404205509303106230}}, taken in [[19w40a]].
** Java Edition 1.16 is {{cd|6006096527635909600}}, taken in [[20w13a]].
** Java Edition 1.18 is {{cd|2151901553968352745}}, taken in [[21w40a]].
** Java Edition 1.19 is {{cd|-1696067516}}, which is the seed resulting from typing {{cd|thewildupdate}} in as a seed, generated in snapshot [[22w15a]].
** Java Edition 1.20 is {{cd|8554477380691140270}}, taken in [[23w14a]].
* The seed for the original [[pack.png]] file is {{cd|3257840388504953787}}, generated in [[Java Edition Alpha v1.2.2|Alpha v1.2.2]], and is also Minecraft [[Bedrock Edition]]'s New UI of Create New World's seed when the seed is not entered or created since [[Bedrock Edition beta 1.18.20.21]]. This seed spawns the player in a {{BiomeLink|Savanna}} Biome in {{cd|-208, 65, 0}}.<ref>https://www.reddit.com/r/MinecraftAtHome/comments/iocx6f/packpng_seed_was_found_explanation_tutorial_and</ref> It can also be generated between [[Java Edition Alpha v1.2.0|Alpha v1.2.0]] and [[Java Edition Beta 1.7.3|Beta 1.7.3]] with minor population differences.
* The seed for the Skull on Fire [[painting]] is either {{cd|-6984854390176336655}} or {{cd|-1044887956651363087}}, generated in [[Java Edition Alpha v1.1.2_01|Alpha v1.1.2_01]] or prior.<ref>https://www.reddit.com/r/Minecraft/comments/iqg3ey/the_original_screenshot_seed_of_the_minecraft/</ref>
* The seed used for the original [[Herobrine]] doctored screenshot is {{cd|478868574082066804}}, generated in [[Alpha v1.0.16_02]].
* The seed used for the original [[Herobrine]] hoax livestream is {{cd|3609313613745973624}}, generated in [[Alpha v1.0.17_04]].

== Technical ==
=== Realms ===
{{IN|java}}, a player can type {{cmd|seed}} in the chat. {{IN|bedrock}}, the seed is not visible when playing on Realms.

=== General ===
If the seed contains characters other than numbers or is greater than or equal to 20 characters in length, the Java <code>String.hashCode()</code> function is used to generate a number seed. This restricts ''Minecraft'' to a subset of the possible worlds to 2<sup>32</sup> (or 4,294,967,296), due to the {{cd|int}} datatype used. Number seeds or a default world seed must be used to access the full set of possible worlds (2<sup>64</sup>, or 18,446,744,073,709,551,616).

=== Overlap between editions ===
All ''Java'' and Bedrock Edition seeds in the range from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 (64-bit seeds), generate the same terrain and [[biome]]s in both ''Java'' and Bedrock editions, although with differing structures, decorator placements, carver caves, and mob spawns.

===Generation quirks ===
{{info needed section|Explain these phenomena considerably more in depth}}
Through certain seeds, it is possible to observe interesting effects.

====Changing terrain without changing some structures ====
Only certain sections of the seed are used to generate specific features within the world. It is possible to generate multiple worlds with identical cave systems, Nether biomes and other arrangements of generated structures simply by converting the seed into binary and tweaking the desired bits.<ref>https://www.minecraftforum.net/forums/minecraft-java-edition/seeds/2229720-can-two-different-seeds-produce-identical-worlds</ref> An example is the seed generator using only the first 48 bits to generate cave systems and badlands clay banding layers.

==== Repetition ====
{{needs update|section=1|Was this fixed in [[Caves & Cliffs]]: Part II? If not, please replace the seeds with the new one.}}
[[File:Duplicate Caves.png|thumb|Seed 164311266871034 in spectator mode. Caves are repetitive along the Z axis.]]
[[File:Endlesscanyon wideangle.png|thumb|Seed 1669320484 in [[Bedrock Edition]], with repeating [[canyon]]s.]]

Certain seeds return 0 in the internal code,<ref>http://stackoverflow.com/questions/3065554/can-javas-random-function-be-zero</ref> causing infinite arrays of [[cave]]s and other structures to generate.<ref>{{bug|MC-111378||Math error (random generation of zero) causing map gen to fail|Won't Fix}}</ref> {{iN|java}}, the seed {{code|107038380838084}} returns 0 on the first call and {{code|164311266871034}} returns 0 on the second call, causing mineshafts, caves and underwater ravines to loop on the X and Z axes respectively.<ref>https://www.reddit.com/r/MCPE/comments/5i6sae/recursive_infinite_mineshaft_seeds_on_mcpe/</ref>

Features in seeds can repeat, such as decorations. These generate diagonally.<ref>{{ytl|UtNXUMrSIxQ|This Minecraft Seed Makes Everything Repeat|Matthew Bolan|January 5, 2020}}</ref>

{{iN|bedrock}}, diagonal cave, ravine, dungeon, and decoration repetition occur with the seeds {{code|289849025}} and {{code|1669320484}}.<ref name="bedrockrepeat">{{bug|MCPE-95011}}</ref> Mineshaft generation repeats vertically in the seeds {{code|-1171867832}} and {{code|1000686894}}.

Any seed calculated as {{code|4294967296 × n + 1669320484}} also generate maps with repeating features.<ref name="bedrockrepeat" />

==Video==
<div style="text-align:center">{{yt|3B3Wgv99wq8}}</div>
<div style="text-align:center">{{yt|CSa5O6knuwI}}</div>

==History==
{{info needed section|Were the seeds always 64-bit integers, or they were 32-bit in older (pre-Infdev) versions?}}
{{needs update|section=true|Bedrock experimental changes}}
{{HistoryTable
|{{HistoryLine|java pre-classic}}
|{{HistoryLine||rd-160052|Added a simple level generator.}}
|{{HistoryLine|java classic}}
|{{HistoryLine||0.0.12a|Added a new level generator.}}
|{{HistoryLine||August 25, 2009|link=wordofnotch:170887079|Showed another new level generator, which generates cliffs more commonly.}}
|{{HistoryLine|java indev}}
|{{HistoryLine||0.31|dev=20091223-1457|Isometric level rendering screenshot added.}}
|{{HistoryLine|||dev=20100106|The player can now select island, floating, flat, or original as the level type when generating a world.
|Players can also select square, long, or deep as the level shape.
|Players can also select small, normal, or huge as the level size.}}
|{{HistoryLine|||dev=20100107|Deep floating maps now have layers of islands.
|Players can now select a level theme; normal or hell.}}
|{{HistoryLine|||dev=20100110|Islands now generate with more sand.}}
|{{HistoryLine|||dev=20100113|Oceans now generate with infinite water.}}
|{{HistoryLine|||dev=20100122|Water now spawns naturally above sea level and on floating islands.|Caves are now less flooded.}}
|{{HistoryLine|java infdev}}
|{{HistoryLine||20100227-1414|Terrain-breaking change to world gen: using any given seed on older versions now generates a different world.
|World generation has been greatly simplified (with the removal of sand, blobs) in order to make infinite world generation implementation easier to work with.}}
|{{HistoryLine||20100227-1433|Brick pyramid generation changed - they now always come to a single point at the top, rather than sometimes being truncated, resulting in "brick square frusta".}}
|{{HistoryLine||20100313|Oceans are considerably larger than before.{{check the code}}}}
|{{HistoryLine||20100320|Reimplemented primitive [[ore (feature)|ore blob]] generation, in which they spawn as scattered, single blocks.
|Reimplemented [[tree]] generation.}}
|{{HistoryLine||20100325|Ore blob generation has been changed to the modern generation type. However, a float is used in their generation, causing their generation to [[Java Edition distance effects/Historical effects|break down at excessive distances.]]
|Added [[cave]]s. They generate through all blocks, not just terrain blocks.}}
|{{HistoryLine||20100327|Terrain-breaking change to world gen: using any given seed on older versions now generates a different world.
|World generation has been significantly overhauled, which is visually very obvious.
|Removed caves.
|Removed [[random patch]]es of flowers.
|The large stone wall at 33,554,432 no longer generates. Instead, the [[Far Lands]] generate at 12,550,824.}}
|{{HistoryLine||20100413|All trees are now large trees.
|[[Sand]] and [[gravel]] now generate with the world again.}}
|{{HistoryLine||20100420|Terrain-breaking change to world gen: using any given seed on older versions now generates a different world.
|World generation seems considerably less mountainous.}}
|{{HistoryLine||20100608|All trees are now small trees again - big trees do not generate.}}
|{{HistoryLine||20100611|Terrain-breaking change to world gen: using any given seed on older versions now generates a different world.
|Terrain now appears to come in large islands.
|Terrain can now generate high enough to be higher than the world height limit, causing it to be cut off.
|[[Monolith|Monoliths]] now have the potential to generate.
|The amount of trees that generate appears to be different now.}}
|{{HistoryLine||20100616|Terrain-breaking change to world gen: using any given seed on older versions now generates a different world.
|Terrain generation in ocean{{verify}}
|Reimplemented caves.
|Random patches of flowers and [[mushroom]]s now generate.
|[[Spring]]s now generate.
|[[Lava]] now naturally generates, although how it does so exactly is unknown.}}
|{{HistoryLine|java alpha}}
|{{HistoryLine||v1.2.0|dev=preview|Terrain-breaking change to world gen: using any given seed on older versions now generates a different world.}}
|{{HistoryLine|java beta}}
|{{HistoryLine||1.3|It is now possible to manually determine the seed upon world creation.}}
|{{HistoryLine||1.8|dev=Pre-release|Terrain-breaking change to world gen.
|The debug screen now displays the seed number.}}
|{{HistoryLine|java}}
|{{HistoryLine||1.2.1|dev=12w03a|Minor terrain-breaking change to world gen.}}
|{{HistoryLine||1.2.1|dev=12w07a|Seeds can no longer change biomes in existing worlds due to the Anvil file format.}}
|{{HistoryLine||1.2.1|dev=?|Multiplayer servers no longer send the seed to clients.}}
|{{HistoryLine||1.3.1|dev=12w18a|Due to singleplayer becoming multiplayer, the world's seed is no longer displayed on the debug screen.}}
|{{HistoryLine|||dev=12w21a|Added {{cmd|seed}}, which displays the current world seed.}}
|{{HistoryLine||1.7.2|dev=13w36a|Terrain-breaking change to world gen with the introduction of many new biomes.}}
|{{HistoryLine||1.13|dev=18w06a|World generator rewritten in a mostly non-breaking way.}}
|{{HistoryLine||1.18|dev=1.18 Experimental Snapshot 1|Terrain-breaking change to the world gen with the introduction of multinoise, terrain noise, biome builders, and new caves.
|Seed limit is now 48-bit.<ref name="MC-236650">{{bug|MC-236650}}</ref>}}
|{{HistoryLine|||dev=1.18 experimental snapshot 2|World generator rewritten in a non-breaking way.}}
|{{HistoryLine|||dev=21w41a|Replaced the random number generator used in world generation, which reverted the seed limit back to 64-bit.<ref name="MC-236650"/>
|Seeds have been reshuffled due to this change. Worlds no longer look like they did in previous snapshots.}}
|{{HistoryLine|||dev=21w43a|Seeds have been reshuffled again. Worlds no longer look like they did in previous snapshots.}}
|{{HistoryLine||1.18.2|dev=22w03a|The seed "0" (zero) can now be used normally.
|Any spaces before or after an inputted seed is now trimmed.}}

|{{HistoryLine|pocket alpha}}
|{{HistoryLine||v0.1.0|Added seeds (32 bit).}}
|{{HistoryLine||v0.7.2|The seed for each world is now displayed in the [[world selection menu]] when the "Edit" button is pressed.}}
|{{HistoryLine||v0.9.0|dev=build 1|Terrain-breaking change to world gen: using any given seed on older versions now generates a different world.}}
|{{HistoryLine||v0.11.0|dev=build 7|The seed is now displayed at the top of the screen in development versions while the player is in a world.}}
|{{HistoryLine||v0.11.0|Before this update, the game would use a Unix timestamp as the seed if no other seed was typed. From this update onwards, it uses a random number generation.}}
|{{HistoryLine|bedrock}}
|{{HistoryLine||1.18.0|dev=beta 1.18.0.20|Terrain-breaking change to the world gen. Revamp [[Cave]]s, [[Mountains]], and [[Terrain]] height system.}}
|{{HistoryLine|||dev=beta 1.18.0.22|Replaced the random number generator used in world generation, resulting in different terrain being generated using same seed.}}
|{{HistoryLine|||dev=beta 1.18.0.24|Seeds have been reshuffled again. Worlds no longer look like they did in previous betas.}}
|{{HistoryLine||1.18.30|dev=beta 1.18.20.21|Worlds can now be created with 64-bit seeds.
|Single-digit seeds such as "0" can now be used normally.}}

|{{HistoryLine|legacy console}}
|{{HistoryLine||xbox=TU1|xbone=CU1|ps3=1.00|psvita=1.00|ps4=1.00|wiiu=Patch 1|switch=1.0.1|Added seeds (64-bit).}}
|{{HistoryLine||xbox=TU5|Terrain-breaking change to world gen.}}
|{{HistoryLine||xbox=TU12|Minor terrain-breaking change to world gen. Biome info is now saved to worlds instead of recalculated when biome generation changes.}}
|{{HistoryLine||xbox=TU31|xbone=CU19|ps3=1.22|psvita=1.22|ps4=1.22|wiiu=Patch 3|Terrain-breaking change to world gen.}}
|{{HistoryLine||xbox=TU54|xbone=CU44|ps3=1.52|psvita=1.52|ps4=1.52|wiiu=Patch 24|switch=1.0.4|Added Biome Scale slider and Find Balanced Seed option.}}
|{{HistoryLine|3ds}}
|{{HistoryLine||0.1.0|Added seeds (32 bit).}}
}}

== References ==
{{Reflist}}

== External links ==
=== Bedrock and Java Editions ===
* [http://chunkbase.com/apps/ '''Chunkbase Minecraft Apps''': Online seed/map explorer tool]
* [https://www.reddit.com/r/minecraftseeds/ '''Minecraft Seeds on Reddit''': Community-driven Minecraft Seeds]
* [https://minecraft-seeds.net '''Minecraft Seeds''': Community-driven Minecraft Seeds]
* [https://lookingforseed.com '''LookingForSeed''': Find Minecraft seeds from various categories]
* [https://minemap.org/ '''Minemap.org''': High resolution maps for good seeds for the ''Java'' and Windows 10 (Bedrock) Edition]

=== Java Edition only ===
* [https://github.com/thedarkfreak/Minecraft-Save-Seed-Reader/wiki '''Random Seed Reader''': Local Java tool]
* [https://seedhunt.net/advanced '''Minecraft SeedHunt''': Selected Seeds from various categories for Java 1.16]
* [http://minecraftgames.co.uk/seeds/ '''Minecraft Seeds Java Edition''': New Seeds for 1.16.4 Version]
* [https://github.com/KaptainWutax/SeedCracker '''SeedCracker''': guess a seed from a multiplayer server]
* [https://www.mcseeder.com/ '''Seeder''': Seed/map explorer tool and finder for ''Java'']

== Navigation ==
{{Navbox Java Edition technical|general}}
{{Navbox Bedrock Edition}}

[[cs:Zdroj]]
[[de:Startwert]]
[[es:Semilla (generación de mundo)]]
[[fr:Graine (génération du monde)]]
[[ja:シード値]]
[[ko:시드]]
[[nl:Seed (wereldgeneratie)]]
[[pl:Ziarno generatora]]
[[pt:Semente (geração de níveis)]]
[[ru:Зерно (генерирование мира)]]
[[uk:Зерно (генерація світу)]]
[[zh:种子（世界生成）]]
