Debug screen (2023)

The debug screen is triggered when the F3 key is pressed. It shows the chunk cache, the memory usage, various parameters, the player's map coordinates and a graph that measures the game's current frame rate.

When the reducedDebugInfo gamerule is set to true, only the starred items are included, in order from top to bottom. The left side is more about the actual game and the right side is more about the player's system information.

NameDescription[1][2]Version*Displays the version, whether it is vanilla or not, or whether it is a snapshot or not.fps*The frame rate in frames per second.T (first)*Shows the max framerate ("inf" if Unlimited) and the Graphics type ("fast" if Fast, "fancy" if Fancy and "fabulous" if Fabulous!), including cloud settings ("fast-clouds" if Fast, "fancy-clouds" if Fancy and none if clouds are off), as well as if the player has VSync turned on or not.B (first)*The player's biome blend setting.GPU*The estimated GPU utilization percentage.ms ticks*The time it takes for a game tick to be processed on the integrated server.tx*Number of packets sent by the client.rx*Number of packets received by the client.C (first)*Number of chunk sections rendered over the total number of chunk sections in the loaded area.D*Client-side render distance.pC*Pending chunks to be batched.pU*Pending uploads to video card.aB*Available buffers to use in the batching process.E*Number of rendered entities over total entities.B (second)*Unused, always 0. May previously have been the number of entities removed due to hidden chunks.[verify]SD*Simulation distance.P*Number of particles in world.T (second)*Displays the total number of entities (including mobs and dropped items) in loaded chunks.Client Chunk Cache*The most chunks that can be loaded on the client.ServerChunkCacheSimilar in how the client stores chunk cache. Made in mind for LAN connections for server caching.[verify]Dimension FCThe current dimension of the player with the count of force loaded chunks (FC = Forceloaded Chunk).XYZX: Player's location in blocks East of 0,0 (negative values are to the West).

Y: Player's (feet) altitude in blocks (63 is Overworld sea level, -54 is overworld lava flood level, 32 is Nether lava sea).
Z: Player's location in blocks South of 0,0 (negative values are to the North).

BlockThe coordinates of the block the player's feet are in, in xyz format. Similar to XYZ as above, rounded down to a whole number. The numbers in square brackets display the location of the player within a chunk.Chunk*The location of the chunk within the world. In reduced mode, only the location within the chunk is displayed. The square brackets contain the chunk position in the region file, and the name of this region file that the player is currently in.FacingThe direction in which a player is facing. Toward Positive X/Z indicates the player's alignment toward the x/z axis. The two numbers at the end indicate the player's horizontal (azimuthal) and vertical (altitudinal) rotation.Client LightThe client-side light values, where a is the sky light level and b is the block light level.

The first number is the total light level where the player's feet are. Note that there are a few caveats here due to the sky light level showing the light level the block would get from the sun in full daylight, but does not account for the lower light levels at night or during a storm.
The second number is the amount of light from the sky at the block the player's feet are in. Same caveat as above.
The third number is the amount of light from other blocks (e.g. torches) at the block the player's feet are in.

CHDescribes the client side heightmaps.

CH: client-side heightmaps
S: WORLD_SURFACE
M: MOTION_BLOCKING

SHDescribes the server side heightmaps.

SH: server-side heightmaps
S: WORLD_SURFACE
O: OCEAN_FLOOR
M: MOTION_BLOCKING
ML: MOTION_BLOCKING_NO_LEAVES

BiomeShows the player what biome they are in.Local DifficultyShows the difficulty of the chunk the player is in. See Difficulty on how this works. The second number in parentheses displays the number of in-game days the player has been in the world.BlendingShows the mode of blending. When player is in a chuck that is generated using old method, this row exists and shows "Old", otherwise doesn't exist.NoiseRouterShows the noise values used to generate terrain and biomes. Displayed only when using the multi_noise biome source.

T: temperature. Used for biome placement, and does not affect terrain.
V: vegetation. Used for biome placement, and does not affect terrain.
C: continentalness. Used to distinguish ocean and land.
E: erosion. How flat the terrain is. Higher values result in flatter biomes, lower values in mountainous biomes.
D: depth. Used for the generation of underground biomes.[verify]
W: weirdness. Used for rivers and, in places with low erosion, to determine if the biome is in a valley, peak, or in between. Also used to determine the placement of unique biomes like sunflower plains and ice spikes.
PV: peaks and valleys. Derived from the weirdness noise value.
AS: its purpose is unknown.
N: its purpose is unknown.

Biome builderCategorizes the noise values used to generate terrain and biomes. Displayed only when using the multi_noise biome source.

PV: peaks and valleys. Can be one of Valley (rivers), Low, Mid, High, or Peak.
C: continentalness. Can be one of Mushroom fields, Deep ocean, Ocean, Coast, Near inland, Mid inland, or Far inland.
E, T, and H: erosion, temperature and humidity, respectively. Represent different ranges of noise values as numbers, where lower numbers are also lower actual values.Temperature and humidity can be 0 to 4, while erosion can be 0 to 6.

SCShows the total amount of mob-spawning chunks (usually 289).M (first)Shows the total amount of monsters that count toward the mob cap.C (second)Shows the total amount of creatures (passive mobs that spawn on a surface).A (first)Shows the total amount of ambient mobs (bats).A (second)Shows the total amount of axolotls.UShows the total amount of underground water creatures (glow squids).W (first)Shows the total amount of water creatures (squids and dolphins).W (second)Shows the total amount of water ambient mobs (all 4 types of fish).M (second)Shows the total amount of misc entities.SoundsRepresented by: Number of sounds playing/maximum of sounds playing.

The first pair represents normal sounds like breaking or placing a block, moving or burning fire.
The second pair represents streamed sounds, such as music, music from music discs, and loop ambience sounds.
The mood value in parentheses indicates how close the player is to the next mood ambience sound being played (see Ambience#Mood algorithm).

ShaderThe file path of the currently-active shader (within the "assets" directory of minecraft.jar). Displayed only if a shader is active.Debug*Tells the player whether the debug pie, or the FPS + TPS graphs are visible or not.For help*Tells the player to press F3 + Q for extra debug information; see below for more info.
NameDescriptionJava*The Java version the player is running and whether it is 32bit or 64bit.Mem*The amount of memory that the game uses (as a percent as well), over the max amount of memory the game can use.Allocation Rate*The rate of heap memory that the game allocates, in MB/s.Allocated*The amount of memory the game has allocated from the max the game can use, also as a percent.CPU*The CPU, including how many cores it has, what brand, its exact model and at what speed the CPU runs (in GHz) that the player uses.Display*The resolution of Minecraft (as well as the name of the GPU company), the graphics card, the OpenGL version and what driver the player uses.Targeted BlockDisplays exactly what block the player is targeting, the block's coordinates & blockstates and what tags it has. Appears only when the player is looking at a block.Targeted FluidDisplays exactly what fluid the player is targeting, the fluid's coordinates & blockstates and what tags it has. Appears only when the player is looking at a block or fluid. If the player is targeting a non-fluid block, displays "minecraft:empty" instead.Targeted EntityDisplays exactly what entity the player is targeting, nothing else. Appears only when the player is looking at an entity.

Pie charts in the lower right of the ⇧ Shift + F3 debug screen display real-time profiling information. More detailed information about one section can be displayed by using the keys 1-9. Press 0 to go back to the previous section.

Bar chart in the lower left of the Alt + F3 debug screen displays real time measurement of milliseconds per frame with lines marking 16.7 and 33.3 milliseconds per frame, corresponding to 60 and 30 FPS respectively. The graph is color coded from green to yellow to red, with green being faster frame time, red being slower frame time, and yellow in between. In singleplayer and self-hosted LAN worlds (i.e. when running an integrated server), another graph, at the bottom right, shows milliseconds per tick (MSPT) with a line marking 50 MSPT, which is the maximum amount of time a game tick can take while maintaining 20 ticks per second (the intended rate). The color-coding is similar to the FPS graph.

Text appears in chat for most debug keys listed here. Note that when using a specific key combination like F3 + N, F3 + B, etc., the debug screen does not open.

When the reducedDebugInfo gamerule is set to true, the effects of F3 + B (entity hitboxes), F3 + G (chunk boundaries), F3 + C (copying coordinates), and F3 + I (copying block/entity data) are not shown. Holding down F3 + C to initiate a crash still works as expected, as well as Ctrl + F3 + C.

Java Edition Classic0.0.2aThe version number is now displayed in the top-left corner.Includes the fps and chunk updates.0.0.23aAdded an option to turn on the debug screen. The current version name is always displayed even when the option is disabled.Java Edition Indev0.3120100202Added "E" entities value, "P" particles value, and "LT" value.Upon placing chests, the second value of "LT" would go up upon every chest placed.The first value seemingly is unaffected by this.20100206Removed "LT" value.FPS and chunk updates have been moved next to the version number and are now contained within parentheses.Moved "E" value below "C" value, and moved "P" value below "E" value."C", "F", "O", "B", "I", and "T" values have been added."C" values cover rendered/total chunks, "F" values are chunks outside the field of view, "O" values are chunks culled by occlusion culling, "B" values are culled entities that are hidden in a chunk and can't be seen, "I" values are individually culled entities, and "T" values are terrain and lighting data.20100212-1Added "L" lighting updates value.20100212-2Added Free memory and Allocated memory.Displayed in §8 (dark gray) color code.It always displays even when the option to turn on the debug screen is disabled.20100213Free memory and Allocated memory now display in §7 (light gray) color code.Now only displays when the option is enabled.Java Edition Infdev20100227-1Removed "L" value."T" value no longer displays a value."O", "E", "B", and "I" values no longer function.20100316"E" and "I" values now function again.20100413Added "All" and "Counted" values."All" displays the total number of loaded entities."Counted" seemingly serves the same function as "All".20100420Removed slash from "All" value.Removed "Counted" value.20100624Added second "E" value.Second "E" is located right next to "O" value.Second "E" displays number of empty chunk sections which may be skipped due to not yet being loaded and rendered, or has nothing to draw in the current render pass; all render passes are counted.Lagometer added.Separate from debug screen, requires F6 to be held down and can be displayed with the debug screen.20100627Changed Free memory to Used memory.Now displays MB in parentheses right next to the value percentage.Java Edition Alphav1.1.1The debug screen is no longer listed as an option and now requires F3 to be held down to activate.v1.2.0?The lagometer is now part of the debug screen.v1.2.3The coordinates have been added to the debug screen.Java Edition Beta1.3The debug screen, along with other function key controls, has now become a toggle.When the debug screen is open, it now shows numbers above every mob; these numbers being the mob's Entity ID. These numbers are visible through blocks, making F3 a useful mob-finder.1.7The "f" coordinate has been made visible in the debug screen (facing direction).1.8Pre-releaseThe ability to see the level's seed has been added to the debug screen.Entity numbers being shown above a mob's head have been removed from the debug screen. Some players felt that it was cheating and that it took away from the game.Java Edition1.0.0October 2, 2011The first images of a runtime performance profiler with a pie chart is revealed.Beta 1.9 Prerelease 3The profiler has been added to the debug screen.1.2.11.2Information about the biome and light level of the player's location have been added to the debug screen. The seed in multiplayer has been made hidden from the debug screen and now shows as "0".1.2.4Pressing F3 (Fn + F3 on Mac and some laptops) brings up the debug screen, but without the graphs. The graph appears upon pressing ⇧ Shift + F3 (Fn + ⇧ Shift + F3 on Mac and some laptops).1.3.112w18aInformation about the player's speed and whether the player is touching the ground have added to the debug screen.Coordinates within the debug screen are now rounded to 5 digits.12w21aInformation about the world's seed has been removed from the debug screen, seen instead by pressing the chat key and typing /seed.The frame time graph has been removed from the debug screen.12w30aThe y coordinate now shows both the feet level and the eye level.1.4.212w39aFl, x and z chunk coordinates, and more rotation (f) information have been added to the debug screen.12w41a⇧ Shift + F3 now shows the profiler graph in the debug screen.F3 + H now shows durability on damaged tools, weapons and armor pieces.1.4.41.4.3F3 + B now shows the hitbox around entities. At this point, the hitbox is white and opaque and does not have an outline.1.7.21.7.1F3 + B visual changed. The entity hitbox is now completely transparent, with a thin white outline.1.814w02aThe debug screen now shows which axis the player is facing after the cardinal direction: "Toward positive/negative X/Z".14w04aThe crosshair in the debug screen now displays 3 short colored lines to indicate the direction of each axis: x/red, y/green, z/blue.The x coordinate line in the debug screen now appears bold when looking east/west, similarly the z coordinate line now appears bold when looking south/north.14w05aText within the debug screen now has a background.X, y, z, b, bl and other labels within the debug screen have been replaced with more understandable labels."Light" is now the light levels at feet, not eyes.14w06aX, Y, and Z title in the debug screen has been changed from 'Feet' in the previous snapshot, to 'XYZ'.A day counter, which increases by 1 every dawn, has been added to the debug screen.The debug screen now displays regional difficulty: Peaceful starts at 0.00, Easy starts at 0.75, Normal starts at 1.50, and Hard starts at 2.25.The debug screen now displays player rotation in degrees and quadrants.14w11aOn the right-hand side of the debug screen, a display now shows up if the player is looking at a block, showing its ID and block states.14w17aAll blocks now have their info displayed on the right-hand side of the debug screen.The "Facing negative/positive x/z" from the debug screen has been removed.14w20aThe "Facing negative/positive x/z" has been readded to the debug screen.14w25bF3 + B now also shows which direction entities are looking using a blue line.The line on the right-hand side that had displayed the name of the block model the player was looking at has been removed from the debug screen.14w29aA 'Reduced Debug Info' toggle now exists within multiplayer settings to enable/disable reduced information on the debug screen.The reducedDebugInfo gamerule allows the player to enable/disable reduced information on the debug screen. This overrides all 'reduced debug info' settings in clients.14w30aThe debug screen now displays how many chunk sections are being rendered currently and how many chunk sections are out of view in percent, the OpenGL version, display size, vendor and GPU."Vanilla" has been added to the version number within the debug screen.1.8.2pre1The frame time graph within the debug screen has been readded and redesigned, so that it can now be activated using Alt + F3.1.915w32aF3 + N now toggles between Creative and Spectator modes, when the player is in either of them. The player needs to be allowed to use /gamemode for this to work.15w43aThe debug screen now shows more information.F3 + Q gives help and shows all F3 + key combinations.F3 + F now increases render distance by 1 (Minimum and Maximum are 2-32).F3 + ⇧ Shift + F now decreases render distance by 1 (Min and Max are 2-32).The debug screen now shows if the pie chart and fps chart are shown on screen.The debug screen now shows text in chat when the player reloads chunks, sounds, etc.The debug screen now does not open when the player uses a specific key combination like F3 + N, F3 + B, etc.F3 + S has been removed from the debug screen, which previously reloaded sounds.F3 + T now reloads all resource pack content, including sounds.Red, blue and green lines have now changed in size within the debug screen and now change relative to the GUI scale.The debug screen is now toggled when the F3 key is released, instead of when it is pressed.1.1016w20aF3 + G toggles the visible chunk borders around the player.The 3 lines indicating direction now have a small black outline when looking at an area with bad contrast.1.1318w11aPressing F3 + C now copies the player's current location to the clipboard in the form of a /tp command, though holding for 10 seconds and releasing still forces a debug crash.18w14aThe debug screen now gives a warning before forcing a debug crash.18w22cThe debug overlay now shows the fluid the player is looking at, separately from blocks.pre6F3 + I copies block or entity data to the clipboard.Added information about the time it takes for a tick on the integrated server, number of packets sent by the client (tx), and number of packets received by the client (rx).pre7Added "Looking at liquid" row, which displays the targeted fluid's coordinates."Looking at" row within the debug screen has been renamed to "Looking at block"."Targeted Block" information now targets through fluids. It displays information for blocks up to 16 blocks away.Added "Targeted Entity", which displays information for entities up to 16 blocks away.F3 + I[note 1] has been changed to now be ⇧ Shift + F3 + I. It is now clarified that it copies the client-side data of targeted block or entity. It still can be used by anyone.Added F3 + I to copy targeted block or entity server-side data to clipboard. It can be used only by operators.1.13.118w30aAdded Ctrl + F3 + C to force a JVM crash, instead of a regular crash.18w31aAdded new fields for the current dimension and the related force loaded chunks.1.1418w43cPressing Alt + F3 now shows TPS (ticks per second).Added min/avg/max tick times to help find stutters.1.14.1Pre-Release 1Pressing F3 + Esc now toggles pause without pause menu (if pausing is possible).Pressing F3 + N when in Survival or Adventure mode now changes the player into Creative mode, if cheats are enabled.1.1519w38aThe chunk update counter has been removed from the debug screen.1.15.2Pre-Release 1F3 + D no longer clears recently typed messages and commands from and .1.1620w18aThe "Looking at block" and "Looking at fluid" were integrated into "Targeted block" and "Targeted fluid" located on the right side of the debug screen.Added a new line detailing mob spawning in different categories.20w20aAdded gamemode switcher accessible with F3 + F4.F3 + N now toggles between Spectator mode and the previous gamemode.1.1721w11aAdded F3 + L to generate Performance Metrics.1.18Experimental Snapshot 1Added two new lines: Multinoise and Terrain.1.18.222w03aNow contains the chunk position in the region file, and the name of this region file that player is currently in, in the end of the "Chunk" row.Moved the location of the player within a chunk from "Chunk" row, into the new square brackets at the end of the "Block" row.22w07aMerged the "Terrain" and "Multinoise" row into the "NoiseRouter" row.1.1922w11aAdded estimated GPU utilization percentage to performance profiling metrics and F3 debug screen, available only for graphics devices that support GPU timer queries.Added "Blending" row, above the "Noise Router" row.The H for "humidity" has been changed for a V for "vegetation".22w12aRemoved the F3 + F and F3 + ⇧ Shift + F hotkeys that change render distance.22w16aAdded "Allocation Rate" row, which shows heap memory allocation rate.1.19.11.19.1-rc1The "Blending" row now disappears when the chunk that the player is in uses the new method, instead of displaying "Blending: New".Upcoming Java Edition1.19.4Pre-release 3Pressing F3 + S will now dump contents of dynamic textures (like atlases, maps, etc.) to screenshots/debug/.
NameDescription[4][5]CNumber of chunk sections rendered over total number of chunks. Counts all render passes: if a chunk section is rendered twice (because it contains both water and normal blocks, for example) then it is counted twice.FNumber of chunk sections loaded outside the viewing distance. Counts all render passes.ONumber of chunk sections removed through occlusion culling. Counts all render passes.E (first row)Number of empty chunk sections. These sections are skipped for one of two reasons: Either the chunk has not yet been loaded and rendered into polygons, or the section has nothing to draw in the current render pass. Counts all render passes.E (second row)Number of rendered entities over total entitiesBUnused, always 0.INumber of invisible entitiesPNumber of particles on screenTDisplays the player's max framerateALLDisplays the total number of loaded entities (including mobs and dropped items)ServerChunkCache
ChunkCacheThe most chunks that can be loadedxPlayer's location in blocks East of 0,0 (negative values are to the West) and after the // is the player's chunk number with the block within the chunk in ()yPlayer's altitude in blocks (63 (62.9) is overworld sea level, 11 (10.9) is overworld lava flood level, 32 (31.9) is nether lava sea).zPlayer's location in blocks South of 0,0 (negative values are to the North) and after the // is the player's chunk number with the block within the chunk in ()fThe direction in which a player is facing (south=0, west=1, north=2, east=3) and if the player walks toward x or z respectivelylcMax section height for the chunk the player is in (uses cubic chunk sections, so heights display in multiples of 16 minus 1).bShows the player what biome they are in.bl(for "block light") The amount of light from other blocks (e.g. torches) at the block the player's head is in. If the player stands on top of a torch, this field shows a light level of 13 instead of the expected 14, due to the player's head being one block away from it.sl(for sky light) The amount of light from the sky at the block the player's head is in. Note that the number shown here is accurate only during the day. It shows the light level the block would get from the sun in full daylight, but does not account for the lower light levels at night or during a storm.rl(for raw light) The total light level where the player's head is, equal to max (bl,sl). Note that because the "sl" field is factored in here, this field has the same caveats as that one.wsWalking speed.fsFlying speed.gOn ground, Boolean value, true if the player touches the ground.flThe y-coordinate of the highest block where the player is able to stand, rounded up when standing on half-blocks, such as slabs. When above the void (where there is no block), it equals 0.shaderThe file path of the currently-active shader (within the "assets" directory of minecraft.jar). Displayed only if a shader is active.

Issues relating to "Debug screen" or "F3" are maintained on the bug tracker. Report issues there.

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