Customize is a mode where the player can customize each of the character's costumes separately also with additional items. The customization system started in Tekken 5 and has returned for all subsequent installments. Players can buy customization items for their character with fight money. The fight money is also called "G". Players can earn fight money by doing many battles as they can in different modes.
As of Tekken 6, fight money can also be earned from winning online matches.
In Tekken Tag Tournament 2, fight money can be doubled or tripled due to lucky boxes being received after an online victory. On offline mode, special customization items can be unlocked while playing ghost matches.
There is also some form of a customization mode in Tekken 3D: Prime Edition; however, this mode is only enabled after a certain rank is sustained. Moreover, they're more like palette swaps of their default outfits.
In Tekken Revolution, there are virtually no customization options. Instead, there are outfits for each character that are also palette swaps of most of their customizations from TTT2. Unfortunately, they must be purchased via PlayStation Network.