Experience



Experience can be obtained by gathering Experience Orbs from defeated mobs and players. Experience is used for Enchanting. The experience system has been changed in Snapshot 12w22a.

Behavior
Gathering experience points increases the player's experience level by gradually filling a bar on the bottom of the screen until a new level is achieved when the bar is full. When the player dies, they drop 7 times their level as experience orbs, up to a maximum of 100 points (enough to reach level 6). All the other experience vanishes.

In 1.3 players can get xp from mining and smelting

Experience Orbs will not drop from a mob unless the mob is killed by a player or damaged by the player and then killed by other means; therefore ordinary mob grinders cannot be used for farming experience (although grinders can be designed to funnel monsters to a holding location, and wear them down to one-hit kills). Experience orbs will "float" or glide toward the player if they are 2-3 blocks away.

Mobs will drop a random number of orbs, and the orbs can have different values. However, the total value will always remain within these values, regardless of difficulty setting:



Leveling Up
 XP required,XP diff 0,0 7,7 17,10 31,14 48,17 69,21 93,24 121,28 152,31 187,35 225,38 267,42 312,45 361,49 413,52 469,56 528,59 591,63 657,66 727,70 800,73 877,77 957,80 1041,84 1128,87 1219,91 1313,94 1411,98 1512,101 1617,105 1725,108 1837,112 1952,115 2071,119 2193,122 2319,126 2448,129 2581,133 2717,136 2857,140 3000,143 3147,147 3297,150 3451,154 3608,157 3769,161 3933,164 4101,168 4447,175 4625,178  

Trivia

 * When enchanting, the experience levels used will be subtracted from your current level, not your current XP total. This has important implications for leveling above 50--the levels gained will have a high XP cost, but this will not be preserved. For example, if you are enchanting anything at level 50: if you earn enough experience to get to level 51, then enchant, you will be left at level 1. If you had enchanted first, and collected the same amount of experience afterward, you would have reached level 8.
 * Experience orbs will drop from a mob if it dies within 5 seconds of being hit by a player. This means you can use fall damage by knocking mobs off a cliff.
 * To reach level 50, which is the amount of skill points required to purchase the highest type of enchantment, one would need to gather 4625 experience by defeating 925 hostile mobs.
 * Experience orbs use to despawn if a player slept before collecting them. This meant that if you died at night and slept before collecting your items, the orbs would disappear when you woke up. This has been fixed; if you sleep after you died, your experience will still be there.
 * Using enchantments does not decrease your score (which is shown on death).
 * In the resources folder of Minecraft, there appears to be an unused sound of leveling up. It cannot be heard in gameplay.
 * If you gain too many experience points (such as a trillion through server commands), the experience bar will disappear altogether as well as your level on your HUD. This appears to occur around level 32,767.
 * Dying in the Nether causes enough dropped experience orbs to disappear, that you will have dropped 30 experience levels.
 * As of weekly snapshot 12w04a the Bottle o' Enchanting was added but is only useful for adventure maps since you don't need any experience when enchanting in creative mode in the snapshot 12w05a.
 * One can determine how much experience has been collected to reach a level using the equation:
 * Total Experience = 1.75[Level]2 + 5.00[Level]
 * This equation does not include any experience that is currently filling the experience bar.
 * Additionally, the amount of experience required to advance to the next level can be calculated using the equation:
 * Experience Required = 3.5[Current Level] + 6.7
 * (NOTE: When performing these calculations, answers should be rounded to the nearest integer, using the "Round Half Away From Zero" rules.)


 * From one large slime, the minimum experience you can get from killing it and all the slimes that split from it is 12, 4 from the largest, 2 from the 2 it splits into, and 1 from the 2 each of those split into. The maximum experience possible is if the big slime splits into 4 and each of those medium slimes split into 4, resulting is 28 total experience.

Bugs

 * Experience is not always rewarded after killing an animal/mob/player, this may be due to effects such as "Fire Aspect" for swords which do additional damage and that damage may not be attributed to you. Animals/mobs should give experience 100% of the time if you use a standard sword and the killing blow is yours.
 * When bringing a single player map into a server to, for example, show friends what you made, your experience for your single player will be reset upon bringing the save back into single player.

Upcoming Features
Each level up will potentially reward the player with Skill Points, which Notch has said may be used for buying things such as increased jump height and increased maximum health.

History

 * Experience was originally revealed by Jeb during an interview. Jeb released a picture of the 1.8 GUI list, which shows the experience bar, among other things.
 * Experience was added in Beta 1.8 but there was no measurable benefit to gaining Experience Orbs and levels.
 * The ability to spend experience levels for Enchanting items was added in 1.0. Experience requirements were also changed in this update.