How is Bedrock Edition storage different from Java Edition?

Bedrock Edition uses Google's LevelDB database with Zlib compression instead of Anvil region files. Data is stored in key-value pairs with little-endian NBT format instead of big-endian.

Can I edit Bedrock world files directly?

Yes, but you need specialized tools that understand the LevelDB format and little-endian NBT. Always backup your worlds before editing as the format is complex and mistakes can corrupt saves.

What is the chunk key format?

Chunk keys consist of X/Z coordinates (32-bit little-endian integers), optional dimension ID, record type tag, and subchunk index. Keys can be 9, 10, 13, or 14 bytes long depending on the data type.

Where is terrain data stored in Bedrock Edition?

Terrain is stored in SubChunkPrefix records (tag 47) for 16×16×16 subchunks, with different storage versions and compression methods used over different Bedrock versions.

Minecraft Bedrock Edition Level Format Tutorial - LevelDB Database Structure Guide

🗃️ Understanding Bedrock Edition Database Architecture

Minecraft Bedrock Edition uses a completely different storage system compared to Java Edition. Instead of Anvil region files, Bedrock uses Google's LevelDB database with Mojang-specific modifications including Zlib compression and Windows support. This exclusive Bedrock Edition feature enables cross-platform compatibility and efficient data access patterns.

🗄️

LevelDB Database System

Key-value storage with modified LevelDB and Zlib compression

🔑

Chunk Key Format

Complex key structure with coordinates and type tags

📊

Little-Endian NBT

NBT format with little-endian byte ordering

⚡

Cross-Platform Support

Optimized for mobile, console, and Windows platforms

🗄️ LevelDB Database Format

Bedrock Edition uses Mojang's modified version of Google's LevelDB for efficient world data storage.

📍 Database Location

The LevelDB database is stored in the db/ subdirectory of each Bedrock world:

worlds/YourWorldName/db/

Important: The database path passed to LevelDB API is the directory path, not any specific file within it.

🔧 Mojang Modifications

Zlib Compression: Added compression for efficient storage
Windows Support: Cross-platform compatibility
Custom Key Format: Specialized chunk addressing system
Little-Endian NBT: Modified NBT byte ordering

Source Code: Available at github.com/Mojang/leveldb

🔄 Data Organization

LevelDB uses a key-value store where:

Keys: Contain chunk coordinates, dimension, and data type
Values: Store actual chunk data, entities, or metadata
Compression: Zlib compression for space efficiency
Indexing: Fast random access to specific chunks

🔑 Chunk Key Format System

Understanding the binary key structure used to identify and access chunk data in the LevelDB database.

📊 Key Components

1. Chunk Coordinates

Two signed 32-bit little-endian integers

X coordinate (4 bytes) + Z coordinate (4 bytes)

2. Dimension ID (Optional)

32-bit little-endian integer

Omitted for Overworld, 1 for Nether, 2 for End

3. Record Type Tag

One-byte tag specifying data type

See key type tags table below

4. Subchunk Index (Optional)

One byte for SubChunkPrefix records

Values from 0 to 15 for different height levels

🔢 Key Lengths

9 bytes: Overworld chunks (8 bytes coords + 1 byte type)
10 bytes: Overworld subchunks (9 bytes + 1 byte index)
13 bytes: Other dimension chunks (12 bytes + 1 byte type)
14 bytes: Other dimension subchunks (13 bytes + 1 byte index)

🏷️ Chunk Key Type Tags

Complete reference of all record type tags used in Bedrock Edition chunk keys.

Terrain & Biome Data

6 types 🔑

Dec	Hex	ASCII	Name	Description
43	2B	+	Data3D	Heightmap (256×2 bytes) and biome data (varying lengths). Biomes stored as 25 palettes, IDs as integers
44	2C	,	Version	1 byte version identifier - 0 for old worlds, higher values for infinite worlds
45	2D	-	Data2D	Heightmap (256×2 bytes) and 2D biomes (256×1 bytes). Biome IDs as 8-bit integers. No longer written since v1.18.0
46	2E	.	Data2DLegacy	Heightmap (256×2 bytes) and 2D biomes (256×4 bytes). Biome ID in first byte, RGB in final 3 bytes. No longer written since v1.0.0
47	2F	/	SubChunkPrefix	Subchunk version (1 byte) + version-dependent data. Terrain for 16×16×16 subchunk
48	30	0	LegacyTerrain	Block IDs (32768 bytes), meta (32768 nibbles), sky/block light (32768 nibbles each), heightmap (256×1 bytes), 2D biomes (256×4 bytes). Data in XZY order. No longer written since v1.0.0

Entity & Block Entity Data

4 types 🔑

Dec	Hex	ASCII	Name	Description
49	31	1	BlockEntity	List of NBT compound roots - block entity data (little-endian NBT)
50	32	2	Entity	List of NBT compound roots - entity data (little-endian NBT)
51	33	3	PendingTicks	List of NBT compound roots - pending tick data (little-endian NBT)
58	3A	:	RandomTicks	List of NBT compound roots - random tick data (little-endian NBT)

World State & Features

11 types 🔑

Dec	Hex	ASCII	Name	Description
52	34	4	LegacyBlockExtraData	Entry count (4 bytes) + entries (Key 4 bytes, Value 2 bytes). Used for grass in snow layers prior to v1.2.13. No longer written as of v1.2.13
53	35	5	BiomeState	Biome state information for chunk generation
54	36	6	FinalizedState	4 bytes - A 32-bit little endian integer indicating finalization status
56	38	8	BorderBlocks	Education Edition Feature - border block data
57	39	9	HardcodedSpawners	Bounding boxes for structure spawns stored in binary format
59	3B	;	Checksums	xxHash checksums of other chunk records. No longer written as of v1.18.0
61	3D	=	MetaDataHash	Metadata hash for chunk verification
62	3E	>	GeneratedPreCavesAndCliffsBlending	Pre-Caves and Cliffs blending data - Not used
63	3F	?	BlendingBiomeHeight	Biome height blending data - Not used
64	40	@	BlendingData	World blending data for terrain generation transitions
65	41	A	ActorDigestVersion	Actor digest version for entity processing optimization

Legacy & Deprecated Records

2 types 🔑

Dec	Hex	ASCII	Name	Description
55	37	7	ConversionData	World conversion data - No longer used
118	76	v	LegacyVersion	1 byte legacy version - moved to tag 44 in v1.16.100

🎯 Special Database Keys

Non-chunk keys used for player data, world settings, and game features.

Player Data Keys

2 keys 🎯

~local_player

Local player entity data with single NBT compound root

player_

Remote player data with client ID from clientid.txt file (e.g., player_-12345678)

World Data Keys

9 keys 🎯

game_flatworldlayers

Flat world layer configuration in ASCII format (length 20, e.g., "[7,3,3,2]" with length 9)

map_<#>

Map item data for individual maps

portals

Nether portal linkage and coordinate data

structuretemplate

Structure template data for generated structures

tickingarea

Ticking area definitions and boundaries

actorprefix*

Actor/entity prefix keys for entity management

digp*

Dig persistence data for world interactions

map_*

Map data prefixes for cartography

schedulerWT*

Scheduler world tick data for timed events

Village System Keys

4 keys 🎯

VILLAGE__DWELLERS

Village dwellers including villagers, iron golems, and cats

VILLAGE__INFO

Village information including bounding boxes and properties

VILLAGE__POI

Point of interest mapping between villagers and their beds/workstations

VILLAGE__PLAYERS

Player interactions and reputation data with villages

📄 level.dat File Structure

The level.dat file in Bedrock Edition uses uncompressed NBT format with little-endian byte ordering and an 8-byte header.

📋 File Header Format

Bytes 0-3: Version number (little-endian 32-bit integer, currently 10)

Bytes 4-7: File length in bytes (little-endian 32-bit integer, minus header)

Bytes 8+: Uncompressed NBT data in little-endian format

🗂️ NBT Data Fields

Player Abilities & Permissions

8 fields 📄

attackmobs

Byte

1 or 0 (true/false) - true if player can attack mobs

attackplayers

Byte

1 or 0 (true/false) - true if player can attack other players

build

Byte

1 or 0 (true/false) - true if player can place blocks

doorsandswitches

Byte

1 or 0 (true/false) - true if player can interact with redstone

flying

Byte

1 or 0 (true/false) - true if player is currently flying

mayfly

Byte

1 or 0 (true/false) - true if player can fly

mine

Byte

1 or 0 (true/false) - true if player can destroy blocks

op

Byte

1 or 0 (true/false) - true if player has operator commands

World Settings & Generation

7 fields 📄

Generator

Int

World type: 0=Old, 1=Infinite, 2=Flat

RandomSeed

Long

World generation seed

Difficulty

Int

0=Peaceful, 1=Easy, 2=Normal, 3=Hard

GameType

Int

0=Survival, 1=Creative, 2=Adventure, 3=Spectator

commandsEnabled

Byte

1 or 0 (true/false) - true if cheats are enabled

bonusChestEnabled

Byte

1 or 0 (true/false) - true if bonus chest is enabled

spawnMobs

Byte

1 or 0 (true/false) - true if mobs can spawn

Spawn Coordinates & Dimensions

4 fields 📄

SpawnX

Int

X coordinate of player spawn position (defaults to 0)

SpawnY

Int

Y coordinate of player spawn position (defaults to 64)

SpawnZ

Int

Z coordinate of player spawn position (defaults to 0)

Dimension

Int

Current dimension: 0=Overworld, 1=Nether, 2=End

Game Rules & Mechanics

8 fields 📄

keepinventory

Byte

Keep inventory on death game rule

mobgriefing

Byte

Mob griefing game rule

dodaylightcycle

Byte

Daylight cycle game rule

dofiretick

Byte

Fire tick game rule

domobspawning

Byte

Mob spawning game rule

doweathercycle

Byte

Weather cycle game rule

naturalregeneration

Byte

Natural regeneration game rule

pvp

Byte

Player vs player game rule

Time & Weather Data

7 fields 📄

Time

Long

Current time of day in ticks (24000 ticks = 1 day cycle)

currentTick

Long

Current game tick counter

LastPlayed

Long

64-bit Q32.32 Unix timestamp of when world was last played

rainLevel

Float

Current rain intensity level

rainTime

Int

Ticks remaining for current rain state

lightningLevel

Float

Current lightning intensity level

lightningTime

Int

Ticks remaining for current lightning state

Version & Compatibility

5 fields 📄

StorageVersion

Int

Bedrock Edition storage tool version (currently 10)

NetworkVersion

Int

Protocol version of last played version

baseGameVersion

String

Maximum version to load resources from (e.g., 1.16.0 removes newer features)

lastOpenedWithVersion

List

Five integers representing last opened version (e.g., [1, 20, 30, 22, 1])

MinimumCompatibleClientVersion

List

Five integers for minimum compatible client version (e.g., [1, 20, 30, 0, 0])

Education Edition Features

6 fields 📄

educationFeaturesEnabled

Byte

1 or 0 (true/false) - true if Education Edition features are enabled

EducationOid

String

UUID for Education Edition organization identifier

EducationProductId

String

Product identifier for Education Edition licensing

eduOffer

Int

Education Edition world marker (worlds with 1 do not open on Bedrock!)

codebuilder

Byte

Code Builder/MakeCode integration status

immutableWorld

Byte

1 or 0 (true/false) - true if world is read-only

Experimental Features

3 fields 📄

experiments_ever_used

Byte

1 or 0 (true/false) - true if world has experimental gameplay locked

saved_with_toggled_experiments

Byte

1 or 0 (true/false) - true if world has been saved with experiments before

enabled_features

List

List of experimental features enabled for this world

Multiplayer & Network Settings

8 fields 📄

MultiplayerGame

Byte

1 or 0 (true/false) - true if "Multiplayer Game" world setting enabled

MultiplayerGameIntent

Byte

1 or 0 (true/false) - true if "Multiplayer Game" toggle enabled

LANBroadcast

Byte

1 or 0 (true/false) - true if "Visible to LAN players" enabled

LANBroadcastIntent

Byte

1 or 0 (true/false) - true if "Visible to LAN players" toggle enabled

XBLBroadcastIntent

Int

Xbox Live multiplayer exposure: 0=disabled, 1=Invite Only, 2=Friends Only, 3=Friends of Friends

useMsaGamertagsOnly

Byte

1 or 0 (true/false) - true if restricted to Microsoft Accounts only

Platform

Int

Platform identifier (observed value: 2)

PlatformBroadcastIntent

Int

Platform-specific broadcast settings

World Templates & Marketplace

8 fields 📄

isFromWorldTemplate

Byte

1 or 0 (true/false) - true if world created from template

isFromLockedTemplate

Byte

1 or 0 (true/false) - true if created from locked template with unmodifiable options

isWorldTemplateOptionLocked

Byte

1 or 0 (true/false) - true if world options locked until user accepts changes

prid

String

UUID of premium world template for Marketplace worlds

hasLockedBehaviorPack

Byte

Behavior pack lock status

hasLockedResourcePack

Byte

Resource pack lock status

texturePacksRequired

Byte

1 or 0 (true/false) - true if texture packs required to join

ConfirmedPlatformLockedContent

Byte

1 or 0 (true/false) - true if world has platform-specific content

Advanced World Settings

8 fields 📄

NetherScale

Int

Nether coordinate scale (defaults to 8): X nether blocks = 1 overworld block

worldStartCount

Long

Counts game closures since world creation (decreases by 1 each closure)

serverChunkTickRange

Int

Simulation distance for chunk processing

CenterMapsToOrigin

Byte

1 or 0 (true/false) - true if maps centered to grid origin

startWithMapEnabled

Byte

1 or 0 (true/false) - true if new players spawn with locator map

SpawnV1Villagers

Byte

1 or 0 (true/false) - spawn pre-1.10.0 villagers

isCreatedInEditor

Byte

1 or 0 (true/false) - true if created from Bedrock editor

isExportedFromEditor

Byte

1 or 0 (true/false) - true if exported from Bedrock editor

Special Data Structures

7 fields 📄

FlatWorldLayers

String

JSON controlling flat world generation

Default Example:

{ "biome_id": 1, "block_layers": [ { "block_name": "minecraft:bedrock", "count": 1 }, { "block_name": "minecraft:dirt", "count": 2 }, { "block_name": "minecraft:grass_block", "count": 1 } ], "encoding_version": 6, "structure_options": null, "world_version": "version.post_1_18" }

BiomeOverride

String

Makes world single-biome with specified biome ID

InventoryVersion

String

Inventory system version identifier

world_policies

Compound

World-specific policy settings

eduSharedResource

Compound

Education Edition shared resource configuration with buttonName and linkUri

IsHardcore

Byte

1 or 0 (true/false) - true if world in Hardcore mode

IsSingleUseWorld

Byte

1 or 0 (true/false) - unused, may cause world deletion after use

🔄 NBT Format Differences

Key differences between Bedrock Edition and Java Edition NBT data formats.

🔵 Bedrock Edition NBT

Byte Order: Little-endian
Integer Storage: Multi-byte integers in little-endian
String Lengths: Little-endian length prefixes
Compression: Zlib compression in database
Usage: Entity, BlockEntity, PendingTicks records

🟠 Java Edition NBT

Byte Order: Big-endian
Integer Storage: Multi-byte integers in big-endian
String Lengths: Big-endian length prefixes
Compression: Gzip compression for region files
Usage: Anvil region files and level.dat

⚠️ Conversion Warning

NBT data is not directly compatible between Java and Bedrock editions due to byte ordering differences. Specialized conversion tools are required for cross-platform world transfers.

🛠️ Developer Tools & Resources

Essential tools and libraries for working with Bedrock Edition level format and LevelDB databases.

📚

LevelDB Libraries

Programming libraries for LevelDB access:

Mojang LevelDB: Official modified version with Zlib
leveldb-mcpe-java: Java implementation with compression
Python leveldb: Python bindings for database access
Node.js leveldown: JavaScript LevelDB bindings

🔧

World Editors

Tools for editing Bedrock worlds:

Amulet Editor: Cross-platform world editor
MCC Tool Chest: Bedrock-specific editor
Blocktopograph: Mobile world viewer/editor
Universal Minecraft Editor: Multi-format editor

📊

Analysis Tools

Database inspection and debugging:

LevelDB dump: Database content exploration
NBT parsers: Little-endian NBT readers
Chunk analyzers: Key format decoders
Performance profilers: Database optimization tools

🔄

Conversion Utilities

Format conversion and migration:

Java to Bedrock converters: Cross-edition world transfer
NBT format converters: Endianness conversion
Structure exporters: Cross-platform building
World optimizers: Database cleanup and repair

📋 LOG Files Format

LevelDB generates LOG files in the db/ directory for database operations and compaction processes.

📍 File Location

LOG files are located at the /db path of a Bedrock world:

                            worlds/YourWorldName/db/LOG

                            worlds/YourWorldName/db/LOG.old

Purpose: Part of LevelDB format, used between compaction of LDB files

📄 Log Format

Each log entry follows a structured format:

YYYY/MM/DD-Hour:Minute:Second.Microseconds ProcessID "Operation"

Components:

Date/Time: When the operation occurred
Process ID: Hexadecimal process identifier
Operation: Description of database operation

📊 Example Log Entries

2014/07/24-22:20:08.400488 4a3638 Recovering log #3

Database recovery operation

2024/09/04-11:45:12.123456 2f1a8c Compaction started

Database compaction process beginning

2024/09/04-11:45:15.789012 2f1a8c Level-0 compaction finished

Compaction process completion

🔧 Common Operations

Recovering log: Database startup and recovery
Compaction: Database optimization and cleanup
Level operations: LSM-tree level management
File operations: SSTable file creation/deletion
Manifest updates: Database metadata changes

🛠️ Troubleshooting with LOG Files

🔍 Corruption Detection

Look for error messages about corrupted blocks or invalid checksums

⚠️ Recovery Issues

Check for "Recovering log" entries that don't complete successfully

💾 Space Problems

Monitor compaction operations for disk space or performance issues

🔒 Lock Problems

Identify database locking issues preventing world access

✅ Best Practices & Safety Guidelines

Essential safety practices when working with Bedrock Edition world databases and level files.

🛡️

Safety First

Always backup worlds before any modifications
Test changes on world copies, not originals
Verify tools compatibility with your Bedrock version
Close Minecraft completely before database editing
Check file integrity after modifications

⚙️

Technical Guidelines

Use correct endianness for NBT data reading/writing
Maintain key format when adding new chunk data
Handle compression properly for Zlib-compressed values
Respect version compatibility between Bedrock releases
Validate chunk coordinates and dimension IDs

⚡

Performance Tips

Batch database operations for efficiency
Close database connections properly after use
Monitor database size and perform cleanup
Use appropriate tools for large-scale operations
Test performance impact of modifications

🔄 Version Compatibility

Bedrock Edition's level format evolves with updates. Always check compatibility between your tools, the world's storage version, and the current Bedrock Edition version. Some features and key types are version-specific and may not work across all versions.