In game design, a target number sets a numerical threshold for the trigger of a resolution mechanic. In its most common form, a target number sets the difficulty of an action, that players must match or exceed in order for their character to succeed in that action.

In order to activate a target number's corresponding mechanic, players may need to:

Target numbers are common in games that use numerical randomisers such as dice or playing cards. In these games, players may need to compare the values on those randomisers (possibly with modifiers based on their traits or situations) to a target number to determine if their characters' actions succeed or fail.

Target numbers can be precisely specified in a game's rules text, derived from a character's statistics, determined by a GM (often with guidance from the rules text), or randomly generated. The last option is particularly common when two characters' actions are in conflict with one another, where the modified dice values of one character can set the target number for the other character to beat.

In games that do not use a binary pass/fail resolution mechanic, the difference between a player's dice roll and the target number is sometimes used to determine degrees of success or failure.
