12w32a (a 1.4 snapshot) introduced a new trade unlocking, locking, and restock system, along with tweaking the quantities of 4 trades for balancing reasons. These changes led to some quantities of trades being discontinued and the ability to obtain an invalid uses value by leveraging the old trade system. These trades were available from the introduction of villager trading in 12w21a (a 1.3 snapshot) to 1.3.2. Besides the 4 trades which had their quantities adjusted, the trades during this range were identical to pre-1.8 trades. Two of the changed trades were on the farmer profession, and the other two were on the librarian profession.
Mechanics
As villagers worked quite differently in these versions compared to their modern counterparts, their trade mechanics may be somewhat unintuitive and confusing. This section serves as a brief overview for unfamiliar players.
Villagers will attempt to generate a new trade in two ways. The first is upon initial spawning, and the second is when the villager's last trade is traded. When the villager attempts to generate a new trade, the following occurs:
Each possible trade has a fixed chance to be added to a list.
After each possible trade has been iterated through, the game will check if the list is empty. If it is, it will insert a gold buy trade for 8-9 gold ingots for 1 emerald.
A random trade is selected from the list.
The villager's current trade list will be searched for a trade that has the following properties:
The first buy slot, second buy slot, and sell items have the same ID as the new trade.
If the second buy slot is empty, the count of the first buy slot of the new trade is less than the found trade.
If the second buy slot is not empty, the count of the second buy slot of the new trade is less than the found trade.
If a matching trade is found, the new trade replaces it. Otherwise, the new trade is added to the end of the trade list.
The effect of the trade replacement mechanic is that if a trade is selected that the villager already has, but has cheaper prices (either less items per emerald for buy trades or less emeralds per item for sell trades), the cheaper trade will replace the more expensive trade. E.g, if a farmer already had a buy trade of 21 wheat for 1 emerald and a buy trade of 18 wheat for 1 emerald was generated, it would replace the existing trade. As the sell item count is not compared, some more cost effective trades do not meet the criteria for replacement. E.g, if a farmer already had a sell trade of 1 emerald for 5 apples, if a sell trade of 1 emerald for 8 apples was generated, it would not meet the criteria for trade replacement.
Whenever the player makes a trade with a villager, the following occurs:
The trade's uses value is increased by one.
If the trade is the last trade in the villager's list, the villager queues a trade generation in 60 ticks.
Otherwise, if the villager has more than one trade and if the trade has been traded more than 3-12 times (this value is randomized each time the trade is used), the "to remove" trade is set to this trade.
When the player leaves the trading GUI, the trade generation counter will begin to count down. When it reaches 0, if the "to remove" trade is set, that trade will be removed from the villager, and a trade generation will occur. As long as the GUI is kept open, the player is free to use a trade as many times as they would like. Do note that the "to remove" trade may be overwritten if another trade sets it before trade generation, as it can only hold a single trade value.
Additionally, a bug with how villager data was serialized to NBT allowed for any trade generation that was queued to be forgotten, and the "to remove" trade to be cleared. If the villager is unloaded and saved to disk before the trade generation counter reaches 0, the villager will not process the trade generation and will clear the "to remove" trade. This will result in the villager not gaining any trades, but it will also prevent any trades from being removed.
Possible Trades
These are all of the trades from the five professions. The 1.4 - 1.7, 1.8 - 1.13, and 1.14 - 25w42a (present) status reveals if the specific trade was available as well during that span of villager trades.
Legend
Availability
Meaning
Unavailable
The items of the trade are not obtainable.
Quantities Unavailable
The items of the trade are available, but only in different counts than the trades available pre-1.4.
Certain Quantities
The items of the trade are available and some of the quantities are available, but other quantities are not.
Available
The trade, including its quantities, are fully obtainable.
Other
Special cases, check the reference for more information.
Professions
When updating farmers to 1.8 and beyond, they have a random chance of being assigned to either a farmer, fisherman, fletcher, or shepherd when a trade generation is performed. When updated to 1.14 and beyond without a trade generation being performed, they will always be farmers.
↑The only quantity available from 1.14 to 25w42a (present) is 20 wheat for 1 emerald.
↑ 3.03.1Damage values are ignored when trading in versions before 14w02a (a 1.8 snapshot), meaning all colors of wool and cooked salmon are accepted.
↑The quantities available from 1.8 to 1.13 are 16-21 wool for 1 emerald, only available on the shepherd career.
↑The only quantity available from 1.14 to 25w42a (present) is 18 wool for 1 emerald, only available on the shepherd career.
↑ 6.06.16.2This trade was added in 12w22a (a 1.3 snapshot) with the introduction of the second buy slot.
↑The only quantity available from 1.8 to 16w32b (a 1.11 snapshot) was 1 emerald for 5 apples. The quantities available from 16w33a to 1.13 are 1 emerald for 5-7 apples. Both only available on the farmer career.
↑The only quantity available from 1.8 to 16w32b (a 1.11 snapshot) was 1 emerald for 6 cookies. The quantities available from 16w33a to 1.13 are 1 emerald for 6-10 cookies. Both only available on the farmer career.
When updating librarians to 1.8 and beyond, they normally can only become librarians upon trade generation, as no variant careers originally existed. However, when cartographers were added in 16w39a (a 1.11 snapshot), pre-1.8 villagers gained the ability to also become cartographers when a trade generation was performed. When updated to 1.14 and beyond without a trade generation being performed, they will always be librarians.
↑ 1.01.1The written book buy trade in 12w22a had a weight of 1.3 instead of the intended 0.3. This discontinues the gold ingot buy trade as any result from java.util.Random.nextFloat() will be less than 1.3, meaning that the written book buy trade is always added to the possible trades list, preventing the gold ingot backup trade from ever being added.
↑Before 12w22a (a 1.3 snapshot), the available quantities were 22-29.
↑The quantities available from 1.4 to 1.7 are 24-35 paper for 1 emerald.
↑The quantities available from 1.8 to 1.13 are 24-36 paper for 1 emerald.
↑The only quantity available from 1.14 to 25w42a (present) is 24 paper for 1 emerald.
↑The quantities available from 1.4 to 1.7 are 11-12 books for 1 emerald.
↑ 7.07.1This trade was added in 12w22a (a 1.3 snapshot) with the introduction of the second buy slot.
↑ 8.08.18.28.3Only available for the librarian career.
↑The only quantity available in 1.14 to 25w42a (present) is 1 emerald for 4 glass, only available on the librarian career.
When updating priests to 1.8 and beyond, they will always be priests upon trade generation. When updated to 1.14 and beyond, they will always become clerics.
↑This trade was added in 12w22a (a 1.3 snapshot). 12w21a to 12w21b had the Eye of Ender Buy Trade instead.
↑The only quantity available in 1.14 to 25w42a (present) is 1 emerald for 2 redstone.
↑ 3.03.13.23.33.43.53.63.7Enchantment trades were added in 12w22a (a 1.3 snapshot) with the introduction of the second buy slot. Damage values and NBT data are ignored when trading in versions before 14w02a (a 1.8 snapshot), meaning damaged and enchanted items are accepted.
When updating blacksmiths to 1.8 and beyond, they have a random chance of being assigned to either an armorer, toolsmith, or weaponsmith when a trade generation is performed. When updated to 1.14 and beyond without a trade generation being performed, they will always be armorers.
↑Diamond hoes were enchanted from 19w11a to 1.14. 1.14.1 Pre-Release 1 removed the enchantments, but the quantities are still non-overlapping (quantities unavailable). Only available for the toolsmith career.
↑The only quantity available from 1.14 to 25w42a (present) is 5 emeralds for 1 iron helmet.
↑The only quantity available from 1.14 to 25w42a (present) is 4 emeralds for 1 pair of iron boots.
When updating butchers to 1.8 and beyond, they have a random chance of being assigned to either a butcher or a leatherworker when a trade generation is performed. When updated directly to 1.14 and beyond without a trade generation being performed, they will always be butchers.
↑Damage values are ignored when trading in versions before 14w02a (a 1.8 snapshot), meaning charcoal and Invalid Data Value Coal are accepted.
↑ 2.02.12.2 Only available for the butcher career.
↑ 3.03.13.2Only available for the leatherworker career.
↑The only quantity available from 1.14 to 25w42a (present) is 6 emeralds for 1 saddle.
Invalid Uses Count
Normally, a villager cannot have a trade with a uses value greater than the maxUses value. However, as maxUses did not exist before 1.4, the game defaults to assigning a maxUses value of 7 upon updating, which can be abused to break this rule. 1.3 allows any trade to potentially be used up to 12 times without it being removed, but when a villager has only a single trade unlocked, it is not allowed to be removed regardless of the amount of times it is used. This allows the player to increase the uses of a trade to an arbitrarily high number. If one strategically trades other trades to remove them as they generate, in theory the first trade's uses can be increased forever, eventually resulting in overflowing at 2,147,483,647 to -2,147,483,648. A negative uses value allows trading up to 2,147,483,647 times in any version until it eventually increases back to positive integers, but this is highly impractical to achieve.
After updating to 1.4 and beyond, such trades will gain more maxUses as the villager restocks, but it likely will appear to not restock such trades depending on how high uses is. As 1.14 changed how uses and maxUses were utilized, when restocking in 1.14 or above uses will be set back to 0. If the villager does not have a workstation assigned to be able to restock, the invalid uses count will remain permanently.
Retaining
When updating older villagers to newer versions, certain precautions must be taken to preserve their trades. Villagers may mostly be safely be updated from 1.3 to 1.13 without any loss of trades, barring any other miscellaneous entity upgrade issues. However, one should be careful when restocking these villagers from 1.4 to 1.7, as newly generated trades, if they have the same sell item and a lower buy quantity, can overwrite existing trades. Additionally, loading villagers from 13w36a to 13w39b (1.7 snapshots) will cause second buy slot removal. When loaded in any version from 19w11a (a 1.14 snapshot) to 1.14 Pre-Release 3, you must trade at least once, as upon updating to 1.14 Pre-Release 4 or newer, villagers that have 0 experience and that do not have a workstation will revert to unemployed villagers, losing their trades. If a villager is directly updated from before 1.14 Pre-Release 4 to 1.14.1 Pre-Release 1 or newer, this step may be skipped if the villager has at least 4 trades or a 1.8 - 1.13 career level above 1.
As a result of the addition of careers in 1.8, pre-1.8 villagers will default to a career ID of 0. From 1.8 to 1.13, they will maintain this until they restock, where they will be assigned a random career.
Upon updating to 19w11a and above, if the villager still has a career ID of 0, they will always have a specific career assigned, as noted in the possible trades section of this page. Additionally, all trades will gain the priceMultiplier:0.0f tag, which is unique to pre-1.14 trades. This means that no discount will ever be applied to these trades.
Gold Ingot
Emerald
Wheat
Wool[Farmer 3]
Raw Chicken
Cooked Cod[Farmer 3][Farmer 6]
Bread
Melon
Apple
Cookie
Shears
Flint and Steel
Cooked Chicken
Arrow
Gravel[Farmer 6]
Flint
Paper
Book
Written Book
Bookshelf
Glass
Compass
Clock
Eye of Ender
Redstone
Glowstone
Iron Sword
Enchanted Iron Sword
Iron Pickaxe
Enchanted Iron Pickaxe
Iron Axe
Enchanted Iron Axe
Iron Chestplate
Enchanted Iron Chestplate
Diamond Sword
Enchanted Diamond Sword
Diamond Pickaxe
Enchanted Diamond Pickaxe
Diamond Axe
Enchanted Diamond Axe
Diamond Chestplate
Enchanted Diamond Chestplate
Coal
Iron Ingot
Diamond
Iron Shovel
Iron Hoe
Diamond Shovel
Diamond Hoe
Iron Helmet
Iron Leggings
Iron Boots
Diamond Helmet
Diamond Leggings
Diamond Boots
Chainmail Helmet
Chainmail Chestplate
Chainmail Leggings
Chainmail Boots
Raw Porkchop
Raw Beef
Saddle
Leather Cap
Leather Tunic
Leather Leggings
Leather Boots
Cooked Porkchop
Steak