Effect

Status effects are various conditions, which can be either helpful or harmful, that affect an entity. They can be inflicted in various ways throughout the game, including consuming potions and some food items, being in the range of beacons and conduits, and being attacked by or close to certain mobs.

The command allows players to inflict effects upon themselves and other entities.

Behavior
Any entities inflicted by a status effect are affected in various ways for an amount of time. During the effect, swirly particles emanate from the position of the inflicted entity.

On Java Edition, players can open their inventory to see any current status effects afflicted upon them, as well as its level and duration; on Bedrock Edition the same can be done in different ways, depending on the platform: console players can tap left on the dpad, on iOS and Android they can tap directly on the status effect icons, on Bedrock for Windows 10 the default shortcut is. For most effects, higher levels increase the strength of the effect.

Internally, and in the command and potion Amplifier NBT tags, the game stores an "amplifier" value, which is one less than the displayed level. For example, Strength II has an amplifier of 1.

Due to the way this amplifier is stored in NBT, amplifiers of 128 to 255 (levels 129 to 256) in NBT tags (e.g. on potions) are treated as if they were −128 to −1 (levels −127 to 0) respectively. The command initially applies such amplifiers in their positive-valued sense but this is later converted to the negative-valued interpretation, leading to inconsistent results.

Any number of different status effects, including opposing effects such as Strength and Weakness, can be simultaneously active on a player. However, it is not possible to apply the same effect multiple times, even if they are of different levels (e.g. Strength and Strength II). When applying an effect already active on the player, higher levels overwrite lower levels, and higher durations overwrite lower durations of the same level.

Note that even with commands, effects cannot be made to last forever. If an effect is set to an excessively large amount of time, such as 182 hours (655,200 seconds), it displays as "**:**", but still continues ticking down and eventually expires.

All status effects can be removed by drinking milk, dying, being saved from death by a totem of undying, or traveling through the return portal in the End. Singleplayer users with cheats enabled and operators in multiplayer servers can use or  to achieve the same goal.

Trivia

 * If the player puts Blindness and Night Vision together, the screen turns black and only the sun and moon are visible (except in rainstorms or thunderstorms).
 * The maximum health the player can achieve using Health Boost and Absorption is.
 * A player who gets max health using the method above, and then adds Regeneration with the level of 255 while healing to 1034 hearts, sees the view jolt, even in Creative mode, as if taking damage. This also happens when the effect ends.
 * If the player has at least Resistance 5, then they are practically invincible (apart from the command and the void), although the void cannot kill a player with Regeneration 7 or higher.
 * The Wither effect is the only negative effect that can negatively affect both living and undead mobs.
 * The Jump Boost status effect does not make slimes, magma cubes or guardians jump higher
 * Speed allows slimes to jump farther. High levels of speed can make slimes bounce out of view with just one jump.
 * The Levitation status effect normally raises the player into the air, unless the player is in water.
 * When having multiple status effects, the status effects' timer's is reduced by 1 second each simultaneously, regardless of when the player takes another potion. This is because they use the same "seconds counter" that "ticks" every 20 game ticks to save memory. For example, if the player drinks one potion and another different potion that doesn't reset the timer 5.5 (or any non-integer amounts) seconds later, both status effects' timers subtract 1 second from both of them simultaneously.
 * The player can walk/run while having the Levitation effect, especially on level 254.
 * Although the Wither effect is given to the player by being hit by wither skeletons or the wither, the icon shows a normal skeleton head instead of a wither skeleton head.
 * Using makes the player fly in Survival and not jump, when the effect is over in Survival when in midair, hitting the ground causes the player to shoot into the air, resulting in a likely death.
 * When a creeper has a status effect and explodes, it leaves a lingering potion cloud of the effect(s) that it had before it died.
 * The Conduit Power status icon reuses the old heart of the sea texture.