Form IDs (FormIDs) are eight digit hex-numbers which serve as unique identifiers for virtually everything in the game. Every NPC, creature, quest, place, and item has one. They are primarily used with console commands on the PC and are significant in the game data as well.
Base and Reference IDs
Base IDs and reference IDs (BaseIDs/RefIDs) are two types of Form ID that are used to identify the various NPCs, creatures, and items within the game. The BaseID is the unique identifier for a prototype of the object, while the RefID denotes a specific copy of an object in the game. For unique NPCs and specifically placed creatures or items, the BaseID and RefID are fixed, and are usually noted on relevant pages. Non-unique objects, such as randomly spawned creatures or loot, will usually only have a BaseID, since their RefIDs will change at each encounter and for each item.
Console commands normally only accept either a BaseID or a RefID, not both. For example, the command
player.placeatme <BaseID> will create a new copy of an object and place it at the player's position. This is fine with most items or generic creatures. With unique NPCs however, a second copy will usually cause problems with quests and such. In that case, one could move the NPC to the player with the command sequence:
For most items, creating extra copies does no harm, so
player.additem <BaseID> <quantity> can be used to add the desired quantity of items to the player's inventory. Quest-specific items, however, will suffer from the same problems as unique NPCs, since the quest will often be tied to specific RefIDs for objects, not their BaseIDs. Also, RefIDs can only be used if the object in question is loaded into memory; visiting the cell of the object can assure this. See the console article for further commands and uses of form IDs for other types of things.
xx and Add-Ons
The first two digits of form IDs found in add-ons are given as
xx because they may vary depending on the number of active add-ons and their load order. Objects from a specific add-on will generally all have the same two leading digits. So, if Dawnguard is the only add-on you have, and you're not loading any mods, the
xx for Dawnguard IDs would be
02. The specific code is not displayed in the "Data Files" screen, nor in the Creation Kit, but mod managers and other utilities will often show them. From within the game, you can find the correct ID by opening the console and clicking on an object from that add-on, or by using the
help command with an add-on specific object.
Leading digits which are unique are:
00Those IDs are used by the original Skyrim (Skyrim.esm), the prefix doesn't change
01Those IDs are usually used by the Update module (Update.esm)
ffDynamically allocated IDs use this. Since they depend on a specific playthrough, they should not be documented - they will be different for other players.
- IDs are not case sensitive in either the console or the Creation Kit.
- When typing in an ID in the console, you can skip any leading zeroes. For example, the BaseID for gold is
0000000f, so when you want to add 1000 gold to your inventory, all you need to type is
player.additem f 1000.
- Searches and filters within the Creation Kit will match partial IDs.