Experience



Experience can be obtained by gathering Experience Orbs from defeated mobs and players. Experience is used for Enchanting.

Behaviour
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.

Experience Orbs will not drop unless the mob is killed by a player or damaged by the player and then can be 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.

When the player dies, they only drop half of their experience as orbs, rounded down to the nearest point. The other half vanishes. If he dies from fall damage, no experience orbs will be dropped.

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


For any given level, the experience, E, required to achieve the next level n+1 from the current level, n is: E = 7 + roundDown(n * 3.5)

<!--     see below for the math! Note: Didn't know how to put in a square root! :(    http://en.wikipedia.org/wiki/Square_root

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FORMULA TO CALCULATE THE LEVEL 'n' FROM LEVEL 0 THROUG XP 'E'

E                     =   3.5n * (n + 1)                  // dissolve brackets E                     =   3.5n^2 + 3.5n		   // / 3.5 E / 3.5               =   n^2 + n			   // apply quadratic supplements E / 3.5               =   n^2 + n + (1/2)^2 - (1/2)^2	   // solve E / 3.5               =   n^2 + n + 0.5^2 - 0.25	   // + 0.25 E / 3.5 + 0.25        =   n^2 + n + 0.5^2		   // apply the binomial rule E / 3.5 + 0.25	      =   (n + 0.5)^2			   // take square root (E / 4.5 + 0.25)^0.5  =   |n + 0.5|			   // - 0.5 n		      =   (E / 3.5 + 0.25)^0.5 - 0.5

==> (the negative solution of the square root is not considered because you cant      gain negative XP or reach negative levels!)

==> formula for calculating level n from level 0 with the total amount of experience orbs E:  n = (E / 3.5 + 0.25)^0.5 - 0.5

verification: ==> example: defeating the enderdragon from level 0 (with gaining 20.000 experience):

n = (20000 / 3.5 + 0.25)^0.5 - 0.5 n = 5714,2857142857142857142857142857^0.5 - 0.5 n = 75,592894601845445442903307246836 - 0.5 n = 75,092894601845445442903307246836

if you put this in the formula to calculate the XP, you will see...

E = 3.5 * 75,092894601845445442903307246836 * (75,092894601845445442903307246836 + 1) E = 3.5 * 75,092894601845445442903307246836 * 76,092894601845445442903307246836 E = 19999,125

this is how the formula is verified and it is exactly! the anomalous result is due to the rounding of the calculator!

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FORMULA TO CALCULATE THE LEVEL 'n' FROM LEVEL 0 THROUG XP 'E':

problem is most people would put in the level they can see (the number) in the xp bar, so the solutions could vary highly!

E                              = 3.5(x(x + 1) - n(n + 1))    // / 3.5 E / 3.5            	        = x(x + 1) - n(n + 1)	      // + n(n + 1) E / 3.5 + n(n + 1)	       = x(x + 1)	              // dissolve brackets E / 3.5 + n(n + 1)    	        = x^2 + x	              // apply quadratic supplements E / 3.5 + n(n + 1)    	        = x^2 + x + (1/2)^2 - (1/2)^2 // solve E / 3.5 + n(n + 1)             = x^2 + x + 0.5^2 - 0.25      // + 0.25 E / 3.5 + n(n + 1) + 0.25      = x^2 + x + 0.5^2	      // apply the binomial rule E / 3.5 + n(n + 1) + 0.25      = (x + 0.5)^2		      // take square root (E / 2.5 + n(n + 1) + 0.25)^0.5 = |n + 0.5|		     // - 0.5 n	                       = (E / 2.5 + n(n + 1) + 0.25)^0.5 - 0.5 ==> (the negative solution of the square root is not considered because you cant       gain negative XP or reach negative levels!) ==> you see, that you just have to put the calculating of the start level [n(n + 1)] in the brackets!

==> formula for calculating level n from level 0 with the total amount of experience orbs E:  n = (E / 2.5 + n(n + 1) + 0.25)^0.5 - 0.5

verification:

==> example: defeating a 5 blaze from level 5 (with gaining 50 experience):

n = (50 / 3.5 + 5(5 + 1) + 0.25)^0.5 - 0.5 n = (50 / 3.5 + 30 + 0.25)^0.5 - 0.5 n = (50 / 3.5 + 30.25)^0.5 - 0.5 n = 50,25^0.5 - 0.5 n = 7,0887234393789126014778092713543 - 0.5 n = 6,5887234393789126014778092713543

if you put this in the formula to calculate the XP with a certain start level, you will see...

E = 3.5 * (6,5887234393789126014778092713543 * (6,5887234393789126014778092713543 + 1) - 5 * (5 + 1)) E = 3.5 * (6,5887234393789126014778092713543 * (6,5887234393789126014778092713543 + 1) - 30) E = 3.5 * (6,5887234393789126014778092713543 * 6,6887234393789126014778092713543 - 30) E = 3.5 * (44,070148904558978658669971655781 - 30) E = 3.5 * 14,070148904558978658669971655781 E = 49,245521165956425305344900795235

this is how the formula is verified and it is exactly! the anomalous result is due to the rounding of the calculator!

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If you have further questions, send me a mail: fhkriegl@aol.com copyright (c) by kieselnator, 2011 -->

Farming Experience Orbs
Experience orb farming refers to automating the process of getting experience orbs. One method of farming experience is to take a monster spawner and, with water flows, arrange that mobs are dropped just far enough to lose all but one half of a heart of health, so that they can be killed in a single strike by the player.[cite?]

An enclosure that prevents the mobs from damaging the player is often used too.

Trivia

 * Experience orbs will drop from a mob if it dies within 3 seconds being hit by a player. This means you can use fall damage by knocking mobs off a cliff.


 * Experience orbs will despawn if a player sleeps before collecting them. This means if you die at night and sleep before collecting your items, the orbs will disappear when you wake up.
 * Using enchantments does not decrease your score (which is shown on death).
 * In the resources folder of Minecraft, there appears to be a unused sound of leveling up. It cannot be heard in gameplay.
 * If you gain too much experience points (such as a trillion through server commands), the experience bar will disappear altogether as well as your level on your HUD.

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.